Flexible circuits for electrosurgical instrument

ABSTRACT

The disclosure provides a method of manufacturing a flexible circuit electrode assembly and an apparatus manufactured by said method. According to the method, an electrically conductive sheet is laminated to an electrically insulative sheet. An electrode is formed on the electrically conductive sheet. An electrically insulative layer is formed on a tissue contacting surface of the electrode. The individual electrodes are separated from the laminated electrically insulative sheet and the electrically conductive sheet. In another method, a flexible circuit is vacuum formed to create a desired profile. The vacuum formed flexible circuit is trimmed. The trimmed vacuum formed flexible circuit is attached to a jaw member of a clamp jaw assembly.

TECHNICAL FIELD

The present disclosure is related generally to medical devices havingvarious mechanisms for grasping and sealing tissue. In particular, thepresent disclosure is related to medical devices having graspinginstruments that perform sealing procedures by applying electricalenergy via one or more flexible circuit electrodes.

BACKGROUND

In many surgeries, multiple devices are used to perform grasping oftissue, sealing of the tissue using electrical energy or in other casesultrasonic energy. Conductive elements are use to delivering electricalenergy from an energy source to the energy delivery location. Theconductive elements can be bulky and awkward to route though the limitedspace available in the surgical instrument. While several devices havebeen made and used, it is believed that no one prior to the inventorshas made or used the devices described in the appended claims.

SUMMARY

In some aspects, a method of manufacturing a flexible circuit electrodeassembly or a flexible circuit electrode assembly manufactured by thefollowing method is provided:

1. A method of manufacturing a flexible circuit electrode, the methodcomprising: laminating a flexible electrically conductive sheet to aflexible electrically insulative sheet with an adhesive therebetween toproduce a flexible laminate; forming at least one electrode on theflexible electrically conductive sheet; forming at least oneelectrically insulative layer on a tissue contacting surface of theleast one electrode; and separating the at least one electrode from theflexible laminate.

2. The method of example 1, wherein the flexible electrically conductivesheet is selected from any one of copper, gold plated copper, silver,platinum, stainless steel, or aluminum, or alloys thereof.

3. The method of example 1, wherein the flexible electrically insulativesheet is selected from any one of polyimide, polyester, fluorocarbon, orany polymeric material, or any combinations thereof.

4. The method of example 1, wherein forming the at least one electrodeon the flexible electrically conductive sheet comprises etching at leastone electrode on the flexible electrically conductive sheet.

5. The method of example 4, wherein etching comprises: screen printing aprotective barrier on the flexible electrically conductive sheet; andphotoetching away any remaining material which does not make up a finalshape of the at least one electrode.

6. The method of any one of examples 1-5, wherein the at least oneelectrically insulative layer further defines the at least oneelectrode.

7. The method of example 1, wherein the at least one electricallyinsulative layer defines at least one electrically insulative element.

8. The method of example 7, wherein the at least one electricallyinsulative element is configured as a spacer.

9. The method of example 1, wherein forming the at least oneelectrically insulative layer comprises printing a dielectric materialon the tissue contacting surface of the at least one electrode.

10. The method of example 1, wherein forming the at least oneelectrically insulative layer comprises bonding a dielectric cover filmon the tissue contacting surface of the at least one electrode.

11. The method of any one of examples 1-10, further comprising forming aspacer by etching the dielectric cover film bonded to the tissuecontacting surface of the at least one electrode.

12. The method of example 1, wherein forming the at least oneelectrically insulative element comprises printing at least onedielectric nonstick element on a tissue contacting surface of the atleast one electrode.

13. The method of example 12, wherein printing the least one dielectricnonstick element comprises printing an annular wall on the tissuecontacting surface of the at least one electrode, wherein the annularwall defines a cavity.

14. The method of example 1, wherein forming the at least oneelectrically insulative layer comprises printing at least one dielectricnonstick element on a tissue contacting surface of the at least oneelectrode.

15. The method of example 1, wherein forming the at least oneelectrically insulative layer on the tissue contacting surface of the atleast one electrode comprises printing at least one electricallyinsulative element sized and configured to define a predetermined gapbetween opposing jaw members of a clamp jaw assembly.

16. The method of example 1, wherein forming the at least oneelectrically insulative layer on the tissue contacting surface of the atleast one electrode comprises printing at least one electricallyinsulative pattern of electrically insulative elements on the tissuecontacting surface of the at least one electrode.

17. The method of example 1, wherein separating the at least oneelectrode comprises die cutting the at least one electrode from theflexible laminate.

18. The method of example 1, wherein forming the at least one electrodecomprises forming a distal electrode element on a distal end of the atleast one electrode.

19. The method of example 18, wherein forming the distal electrodeelement comprises forming a distal electrode element that iselectrically coupled to the at least one electrode.

20. The method of example 18, wherein forming the distal electrodeelement comprises forming a distal electrode element that iselectrically isolated from the at least one electrode.

21. The method of example 1, wherein forming the at least one electrodecomprises forming at least two electrode segments electrically isolatedfrom each other by a gap.

22. The method of example 1, wherein forming the at least one electrodecomprises forming at least two electrode segments connected by a flexurebearing.

23. The method of example 22, wherein forming the least two electrodesegments connected by the flexure bearing comprises forming the at leasttwo electrode segments spaced apart laterally relative to the flexurebearing on the at least one electrode.

24. The method of example 22, wherein forming the least two electrodesegments connected by a flexure bearing comprises forming the at leasttwo electrode segments are spaced apart longitudinally relative to theflexure bearing on the at least one electrode.

25. The method of example 1, wherein: forming at least one electrode onthe flexible electrically conductive sheet comprises forming a pluralityof electrodes on the flexible electrically conductive sheet; and formingat least one electrically insulative layer on a tissue contactingsurface of the least one electrode comprises forming the at least oneelectrically insulative layer on a tissue contacting surface of each ofthe plurality of electrodes.

26. A flexible circuit electrode formed by a process, comprising:laminating a flexible electrically conductive sheet to a flexibleelectrically insulative sheet with adhesive therebetween to produce aflexible laminate; forming at least one electrode on the flexibleelectrically conductive sheet; forming at least one electricallyinsulative layer on a tissue contacting surface of the least oneelectrode; and separating the at least one electrode from the flexiblelaminate.

27. The flexible circuit electrode of example 26, wherein the flexibleelectrically conductive sheet is selected from any one of copper, goldplated copper, silver, platinum, stainless steel, or aluminum, or alloysthereof.

28. The flexible circuit electrode of example 26, wherein the flexibleelectrically insulative sheet is selected from any one of polyimide,polyester, fluorocarbon, or any polymeric material, or any combinationsthereof.

29. The flexible circuit electrode of example 26, wherein forming the atleast one electrode on the flexible electrically conductive sheetcomprises etching at least one electrode on the flexible electricallyconductive sheet.

30. The flexible circuit electrode of example 29, wherein etchingcomprises: screen printing a protective barrier on the flexibleelectrically conductive sheet; and photoetching away any remainingmaterial which does not make up a final shape of the at least oneelectrode.

31. The flexible circuit electrode of example 30, wherein the at leastone electrically insulative layer further defines the at least oneelectrode.

32. The flexible circuit electrode of example 26, wherein the at leastone electrically insulative layer defines at least one electricallyinsulative element.

33. The flexible circuit electrode of example 32, wherein the at leastone electrically insulative element is configured as a spacer.

34. The flexible circuit electrode of example 26, wherein forming the atleast one electrically insulative layer comprises printing a dielectricmaterial on the tissue contacting surface of the at least one electrode.

35. The flexible circuit electrode of example 26, wherein forming the atleast one electrically insulative layer comprises bonding a dielectriccover film on the tissue contacting surface of the at least oneelectrode.

36. The flexible circuit electrode of any one of examples 26-35, furthercomprising forming a spacer by etching dielectric cover film bonded tothe tissue contacting surface of the at least one electrode.

37. The flexible circuit electrode of example 26, wherein forming the atleast one electrically insulative layer comprises printing at least onedielectric nonstick element on a tissue contacting surface of the atleast one electrode.

38. The flexible circuit electrode of example 37, wherein the at leastone dielectric nonstick element comprises printing an annular wall onthe tissue contacting surface of the at least one electrode, wherein theannular wall defines a cavity.

39. The flexible circuit electrode of example 26, wherein forming the atleast one electrically insulative element comprises printing at leastone dielectric nonstick element on a tissue contacting surface of the atleast one electrode.

40. The flexible circuit electrode of example 26, wherein forming the atleast one electrically insulative layer on the tissue contacting surfaceof the at least one electrode comprises printing at least oneelectrically insulative element sized and configured to define apredetermined gap between opposing jaw members of a clamp jaw assembly.

41. The flexible circuit electrode of example 26, wherein forming the atleast one electrically insulative layer on the tissue contacting surfaceof the at least one electrode comprises printing at least oneelectrically insulative pattern of electrically insulative elements onthe tissue contacting surface of the at least one electrode.

42. The flexible circuit electrode of example 26, wherein separating theat least one electrode comprises die cutting the at least one electrodefrom the flexible laminate.

43. The flexible circuit electrode of example 26, wherein forming the atleast one electrode comprises forming a distal electrode element on adistal end of the at least one electrode.

44. The flexible circuit electrode of example 43, wherein forming thedistal electrode element comprises forming a distal electrode elementthat is electrically coupled to the at least one electrode.

45. The flexible circuit electrode of example 43, wherein forming thedistal electrode element comprises forming a distal electrode elementthat is electrically isolated from the at least one electrode.

46. The flexible circuit electrode of example 26, wherein forming the atleast one electrode comprises forming at least two electrode segmentselectrically isolated from each other by a gap.

47. The flexible circuit electrode of example 26, wherein forming the atleast one electrode comprises forming at least two electrode segmentsconnected by a flexure bearing.

48. The flexible circuit electrode of example 47, wherein forming theleast two electrode segments connected by the flexure bearing comprisesforming the at least two electrode segments spaced apart laterallyrelative to the flexure bearing on the at least one electrode.

49. The flexible circuit electrode of example 47, wherein forming theleast two electrode segments connected by a flexure bearing comprisesforming the at least two electrode segments are spaced apartlongitudinally relative to the flexure bearing on the at least oneelectrode.

50. The flexible circuit electrode of example 26, wherein: forming atleast one electrode on the flexible electrically conductive sheetcomprises forming a plurality of electrodes on the flexible electricallyconductive sheet; and forming at least one electrically insulative layeron a tissue contacting surface of the least one electrode comprisesforming the at least one electrically insulative layer on a tissuecontacting surface of each of the plurality of electrodes.

51. A method of manufacturing a flexible circuit electrode assembly, themethod comprising: vacuum forming a flexible circuit; trimming thevacuum formed flexible circuit; and attaching the trimmed vacuum formedflexible circuit to a jaw member of a clamp jaw assembly.

52. The method of example 51, further comprising: placing the vacuumformed flexible circuit in a molding tool; and molding a substrate tosupport a profile of the vacuum formed flexible circuit.

53. The method of example 52, wherein attaching the trimmed vacuumformed flexible circuit to the jaw member of the clamp jaw assemblycomprises molding the trimmed vacuum formed flexible circuit over thejaw member.

54. The method of example 51, wherein attaching the trimmed vacuumformed flexible circuit to the jaw member of the clamp jaw assemblycomprises adhering the trimmed vacuum formed flexible circuit to the jawmember with adhesive.

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, aspects, andfeatures described above, further aspects, aspects, and features willbecome apparent by reference to the drawings and the following detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the aspects described herein are set forth withparticularity in the appended claims. The aspects, however, both as toorganization and methods of operation may be better understood byreference to the following description, taken in conjunction with theaccompanying drawings as follows.

FIG. 1A shows a surgical instrument in electrical communication with anenergy source, according to one aspect of the present disclosure.

FIG. 1B is a detailed view of the end effector of the surgicalinstrument shown in FIG. 1A, according to one aspect of the presentdisclosure.

FIG. 10 illustrates an example of a generator for delivering multipleenergy modalities to the surgical instrument of FIG. 1A, according toone aspect of the present disclosure.

FIG. 2 illustrates a bipolar flexible circuit electrode assembly thatutilizes the flexible nature of flexible circuit electrode manufacturingprocess to incorporate a variety of lead lengths and active/passivecomponents in the electrode circuit, according to one aspect of thepresent disclosure.

FIG. 3 illustrates a detail view of a bipolar flexible circuit electrodeassembly comprising a short lead length, according to one aspect of thepresent disclosure.

FIGS. 4-9 illustrate a flexible circuit electrode comprising an extendedlead, according to one aspect of the present disclosure, where:

FIG. 4 is a perspective view of a flexible circuit electrode comprisingan extended lead, according to one aspect of the present disclosure;

FIG. 5 is a plan view of the electrically conductive element side of theflexible circuit electrode shown in FIG. 4, according to one aspect ofthe present disclosure;

FIG. 6 is a plan view of the electrically insulative element side of theelectrically conductive element of the flexible circuit electrode shownin FIG. 5, according to one aspect of the present disclosure;

FIG. 7 is a side elevation view of the flexible circuit electrode shownin FIG. 4, according to one aspect of the present disclosure;

FIG. 8 is an elevation view of the flexible circuit electrode shown inFIG. 4 taken from a distal end, according to one aspect of the presentdisclosure; and

FIG. 9 is an elevation view of the flexible circuit electrode shown inFIG. 4 taken from a proximal end, according to one aspect of the presentdisclosure.

FIGS. 10-17 illustrate a flexible circuit electrode 200 comprisingelectrically insulative elements, according to one aspect of the presentdisclosure, where:

FIG. 10 is a perspective view of the electrically conductive side of aflexible circuit electrode comprising at least one electricallyconductive element and at least one electrically insulative element,according to one aspect of the present disclosure;

FIG. 11 is a perspective view of the flexible circuit electrode shown inFIG. 10 showing the electrically insulative element of the electricallyconductive element, according to one aspect of the present disclosure;

FIG. 12 is a plan view of the electrically conductive element side ofthe flexible circuit electrode shown in FIG. 10, according to one aspectof the present disclosure;

FIG. 13 is a plan view of the electrically insulative element side ofthe electrically conductive element of the flexible circuit electrodeshown in FIG. 10, according to one aspect of the present disclosure;

FIG. 14 is a side elevation view of the flexible circuit electrode shownin FIG. 10, according to one aspect of the present disclosure;

FIG. 15 is an elevation view of the flexible circuit electrode shown inFIG. 10 taken from a distal end, according to one aspect of the presentdisclosure;

FIG. 16 is an elevation view of the flexible circuit electrode shown inFIG. 10 taken from a proximal end, according to one aspect of thepresent disclosure; and

FIG. 17 is a detail view of the flexible circuit electrode shown in FIG.10, according to one aspect of the present disclosure.

FIG. 18 illustrates an end effector comprising four flexible circuitelectrodes that can be independently energized and configured to providean offset current path according to one aspect of the presentdisclosure.

FIG. 19 illustrates the end effector shown in FIG. 18 comprising fourflexible circuit electrodes that can be independently energized andconfigured to provide a direct current path, according to one aspect ofthe present disclosure.

FIGS. 20-26 illustrate a segmented offset flexible circuit electrode,according to one aspect of the present disclosure, where:

FIG. 20 is a perspective view of a segmented offset flexible circuitelectrode comprising two electrode segments of the electricallyconductive element side, according to one aspect of the presentdisclosure;

FIG. 21 is a perspective view of the electrically insulative elementside of the segmented offset flexible circuit electrode shown in FIG.20, according to one aspect of the present disclosure;

FIG. 22 is a plan view of the electrically conductive element side ofthe segmented offset flexible circuit electrode shown in FIG. 20,according to one aspect of the present disclosure;

FIG. 23 illustrates a plan view of the electrically insulative elementside of the segmented offset electrically conductive element of theflexible circuit electrode shown in FIG. 20, according to one aspect ofthe present disclosure;

FIG. 24 is a side elevation view of the segmented offset flexiblecircuit electrode shown in FIG. 20, according to one aspect of thepresent disclosure;

FIG. 25 is an elevation view of the segmented offset flexible circuitelectrode shown in FIG. 20 taken from a distal end, according to oneaspect of the present disclosure; and

FIG. 26 is an elevation view of the segmented offset flexible circuitelectrode shown in FIG. 20 taken from a proximal end, according to oneaspect of the present disclosure.

FIGS. 27-33 illustrate a flexible circuit electrode comprisingelectrically insulative elements, according to one aspect of the presentdisclosure, where:

FIG. 27 is a perspective view of a flexible circuit electrode comprisingan array of electrically insulative elements showing the electricallyconductive element, according to one aspect of the present disclosure;

FIG. 28 is a perspective view of the electrically insulative elementside of the electrically conductive element of the flexible circuitelectrode shown in FIG. 27, according to one aspect of the presentdisclosure;

FIG. 29 is a plan view of the electrically conductive element side ofthe flexible circuit electrode shown in FIG. 27, according to one aspectof the present disclosure;

FIG. 30 is a plan view of the electrically insulative element of theelectrically conductive element of the flexible circuit electrode shownin FIG. 27, according to one aspect of the present disclosure;

FIG. 31 is a side elevation view of the flexible circuit electrode shownin FIG. 27, according to one aspect of the present disclosure;

FIG. 32 is an elevation view of the flexible circuit electrode shown inFIG. 27 taken from a distal end, according to one aspect of the presentdisclosure; and

FIG. 33 is an elevation view of the flexible circuit electrode shown inFIG. 27 taken from a proximal end, according to one aspect of thepresent disclosure.

FIGS. 34-35 illustrate an integrated flexible circuit electrodecomprising electrically insulative elements, according to one aspect ofthe present disclosure, where:

FIG. 34 is a perspective view of an integrated flexible circuitelectrode comprising electrically insulative elements showing theelectrically conductive element side of the integrated flexible circuitelectrode, according to one aspect of the present disclosure; and

FIG. 35 is a section view of the integrated flexible circuit electrodeshown in FIG. 34 taken through one of the electrically insulativeelements, according to one aspect of the present disclosure.

FIG. 36 is a schematic diagram of an end effector comprising an upperjaw and a lower jaw and flexible circuit electrodes attached to thecorresponding upper and lower jaws where the flexible circuit electrodescomprise electrically insulative elements (e.g., insulative elements toestablish desired gaps between electrodes in bipolar electrosurgicalinstruments), according to one aspect of the present disclosure.

FIG. 37 is a plan view of the flexible circuit electrode comprising amacro pattern of electrically insulative elements showing the tissuecontacting surface thereof, according to one aspect of the presentdisclosure.

FIG. 38 is a detail view of the flexible circuit electrode shown in FIG.37, according to one aspect of the present disclosure.

FIG. 39 illustrates a flexible circuit electrode comprising a pattern ofelectrically insulative elements, according to one aspect of the presentdisclosure.

FIG. 40 is a detail view of the flexible circuit electrode shown in FIG.39, according to one aspect of the present disclosure.

FIG. 41 illustrates an end effector comprising an upper jaw and a lowerjaw and flexible circuit electrodes attached to the corresponding upperand lower jaws and where the with the flexible circuit electrodeattached to the lower jaw comprises a thermal isolation and a distalelectrode element, according to one aspect of the present disclosure.

FIGS. 42-48 illustrate a flexible circuit electrode comprising a distalelectrode element and electrically insulative elements, according to oneaspect of the present disclosure, where:

FIG. 42 is a perspective view of a flexible circuit electrode comprisinga distal electrode element and electrically insulative elements showingthe electrically conductive element, according to one aspect of thepresent disclosure.

FIG. 43 is a perspective view of the electrically insulative element ofthe of the flexible circuit electrode shown in FIG. 42, according to oneaspect of the present disclosure;

FIG. 44 is a plan view of the electrically conductive element side ofthe flexible circuit electrode shown in FIG. 42, according to one aspectof the present disclosure;

FIG. 45 is a plan view of the electrically insulative element of theflexible circuit electrode shown in FIG. 42, according to one aspect ofthe present disclosure;

FIG. 46 is a side elevation view of the flexible circuit electrode shownin FIG. 42, according to one aspect of the present disclosure;

FIG. 47 is an elevation view of the flexible circuit electrode shown inFIG. 42 taken from a distal end, according to one aspect of the presentdisclosure; and

FIG. 48 is an elevation view of the flexible circuit electrode shown inFIG. 42 taken from a proximal end, according to one aspect of thepresent disclosure.

FIGS. 49-51 illustrate detail views of a lower jaw portion of an endeffector comprising a flexible circuit electrode comprising anon-isolated distal electrode element and electrically insulativeelements, according to one aspect of the present disclosure, where:

FIG. 49 is a perspective view of a electrode comprising a non-isolateddistal electrode element and electrically insulative elements, accordingto one aspect of the present disclosure;

FIG. 50 is a perspective view of the end effector shown in FIG. 49,according to one aspect of the present disclosure; and

FIG. 51 is an elevation view of the end effector shown in FIG. 49 takenfrom a distal end, according to one aspect of the present disclosure.

FIG. 52 is a perspective view of a lower jaw portion of an end effectorcomprising an isolated distal electrode element, according to one aspectof the present disclosure.

FIGS. 53-59 illustrate a flat flexible circuit electrode comprising anupper electrode and a lower electrode, according to one aspect of thepresent disclosure, where:

FIG. 53 is a perspective view of the flat flexible circuit electrodecomprising an upper electrode and a lower electrode coupled by a flexurebearing showing the electrically conductive elements side, which definethe electrodes tissue sealing surfaces, according to one aspect of thepresent disclosure;

FIG. 54 is a perspective view showing the electrically insulativeelement side of the upper and lower flat flexible circuit electrodesshown in FIG. 53, according to one aspect of the present disclosure;

FIG. 55 is a plan view of the electrically conductive elements side ofthe upper and lower flat flexible circuit electrodes shown in FIG. 53,according to one aspect of the present disclosure;

FIG. 56 is a plan view of the electrically insulative element side ofthe upper and lower flat flexible circuit electrodes shown in FIG. 53,according to one aspect of the present disclosure;

FIG. 57 is a side elevation view of the upper and lower flat flexiblecircuit electrodes shown in FIG. 53, according to one aspect of thepresent disclosure;

FIG. 58 is an elevation view of the upper and lower flat flexiblecircuit electrodes shown in FIG. 53 taken from a distal end, accordingto one aspect of the present disclosure; and

FIG. 59 is an elevation view of the upper and lower flat flexiblecircuit electrodes shown in FIG. 53 taken from a proximal end, accordingto one aspect of the present disclosure.

FIGS. 60-66 illustrate a flexible circuit electrode comprising a flexurebearing, according to one aspect of the present disclosure, where:

FIG. 60 is a perspective view of a flexible circuit electrode comprisingupper and lower electrodes coupled by a flexure bearing and in an openconfiguration, according to one aspect of the present disclosure;

FIG. 61 is another perspective view of the flexible circuit electrodeshown in FIG. 60, according to one aspect of the present disclosure;

FIG. 62 is a plan view of the flexible circuit electrode shown in FIG.60, according to one aspect of the present disclosure;

FIG. 63 is a plan view of the flexible circuit electrode shown in FIG.60, according to one aspect of the present disclosure;

FIG. 64 is a side elevation view of the flexible circuit electrode shownin FIG. 60, according to one aspect of the present disclosure;

FIG. 65 is an elevation view of the flexible circuit electrode shown inFIG. 60 taken from a distal end, according to one aspect of the presentdisclosure; and

FIG. 66 is an elevation view of the flexible circuit electrode shown inFIG. 60 taken from a proximal end, according to one aspect of thepresent disclosure.

FIGS. 67-69 illustrate a vacuum formed flexible circuit electrode,according to one aspect of the present disclosure, where:

FIG. 67 is a perspective view of an end effector comprising a vacuumformed flexible circuit electrode, according to one aspect of thepresent disclosure;

FIG. 68 is a vacuum formed flexible circuit electrode that can beinserted in an injection molding tool, according to one aspect of thepresent disclosure;

FIG. 69 is a vacuum formed flexible circuit electrode that can beadhered directly to a jaw of the end effector jaw assembly shown in FIG.67, according to one aspect of the present disclosure.

FIGS. 70-72 illustrate a comparison of a thin, copper flexible circuitelectrode and a conventional stainless steel electrode from thestandpoint of self-heating, according to one aspect of the presentdisclosure, where:

FIG. 70 illustrates a flexible circuit electrode, according to oneaspect of the present disclosure;

FIG. 71 illustrates a flat conductive trace for a flexible circuitelectrode, according to one aspect of the present disclosure; and

FIG. 72 is a comparison of a conventional stainless steel electrodeversus a thin copper flexible circuit electrode, according to one aspectof the present disclosure.

FIGS. 73-80 illustrate mass produced a cost effective flexile circuitelectrode sub-assembly with insulative barrier along with non-conductivestand-offs, according to one aspect of the present disclosure, where:

FIG. 73 is a perspective view of an assembly comprising an array offlexible circuit electrodes, according to one aspect of the presentdisclosure;

FIG. 74 is an elevation view of the assembly shown in FIG. 73, accordingto one aspect of the present disclosure; and

FIG. 75 is a detail plan view of the assembly shown in FIG. 73 showingindividual flexible circuit electrodes fixed in a carrier web prior todie cutting, according to one aspect of the present disclosure.

FIG. 76 is a perspective view of an assembly comprising an array offlexible circuit electrodes in a carrier web, according to one aspect ofthe present disclosure;

FIG. 77 is a detail view of the array of flexible circuit electrodes ina carrier web shown in FIG. 76, according to one aspect of the presentdisclosure;

FIG. 78 is an individual flexible circuit electrode sub-assembly in acarrier web prior to die-cutting, according to one aspect of the presentdisclosure;

FIG. 79 is a detail view of the individual flexible circuit electrodesub-assembly in a carrier web shown in FIG. 78, according to one aspectof the present disclosure; and

FIG. 80 is an individual flexible circuit electrode sub-assembly shownin FIG. 78 after die cutting and ready to be bonded to a jaw of an endeffector, according to one aspect of the present disclosure.

FIGS. 82-87 describe a thermal assist end effector, according to oneaspect of the present disclosure, where:

FIG. 82 is a perspective view of an end effector jaw assembly comprisingan electrode and a thermal assist heater, according to one aspect of thepresent disclosure;

FIG. 83 is a graphical depiction of power, voltage, and current versusimpedance, according to one aspect of the present disclosure;

FIG. 84 is a schematic of a circuit of an RF drive source with a lowimpedance load between two electrodes, according to one aspect of thepresent disclosure;

FIG. 85 is a schematic of a circuit comprising an RF drive source with alow impedance load between the electrodes, a heater, and a thermalassist control circuit, according to one aspect of the presentdisclosure.

FIG. 86 is a graphical depiction of impedance (14 and power (P) versustime (t), according to one aspect of the present disclosure.

FIG. 87 is logic flow depicting a process for operating the thermalassist control circuit shown in FIG. 85, according to one aspect of thepresent disclosure.

FIGS. 88-91 illustrate an optical force sensor based on a measuringlight transmission through micro-bent polymer optical fibers (POF)embedded in an elastomer strip, according to one aspect of the presentdisclosure, where:

FIG. 88 is an optical force sensor in a relaxed state, according to oneaspect of the present disclosure;

FIG. 89 is a cross section of the optical force sensor shown in FIG. 88in a relaxed state, according to one aspect of the present disclosure;

FIG. 90 is a cross section of the optical force sensor shown in FIG. 88in a compressed state, according to one aspect of the presentdisclosure; and

FIG. 91 is a simplified schematic diagram of the optical force sensorshown in FIG. 88, according to one aspect of the present disclosure.

FIGS. 92-93 illustrate polymer optical fibers (POF) integrated withflexible circuit electrodes for sensing a pressure in a jaw of an endeffector, according to one aspect of the present disclosure, where:

FIG. 92 is a section view of a lower jaw of an end effector comprising apolymer optical fiber (POF) based force sensor, according to one aspectof the present disclosure; and

FIG. 93 is a section view of the end effector shown in FIG. 92 withtissue disposed on the polymer optical fiber (POF) based force sensor,according to one aspect of the present disclosure.

FIGS. 94-97 illustrate flat patterned flexible circuit electrodescomprising a flexure bearing, according to one aspect of the presentdisclosure, where:

FIG. 94 is a flat patterned flexible circuit electrode in a flat statewhere upper and lower jaw electrode elements are in transverseorientation relative to a longitudinal element, according to one aspectof the present disclosure; and

FIG. 95 illustrates the flat patterned flexible circuit electrode shownin FIG. 94 in a folded state where the upper and lower jaw electrodeelements create a flexure bearing, according to one aspect of thepresent disclosure.

FIG. 96 is a flat patterned flexible circuit electrode in a flat statewhere upper and lower jaw electrode elements are in parallel orientationrelative to a longitudinal element, according to one aspect of thepresent disclosure; and

FIG. 97 illustrates the flat patterned flexible circuit electrode shownin FIG. 96 in a folded state where the upper and lower jaw electrodeelements create a flexure bearing, according to one aspect of thepresent disclosure.

FIGS. 98-99 illustrate a flexible circuit integrated comprising anintegrated slider switch to control switching modes, according to oneaspect of the present disclosure, where:

FIG. 98 is a side elevation view of a flexible circuit electrodecomprising an integrated slider switch, according to one aspect of thepresent disclosure; and

FIG. 99 is a plan view of the flexible circuit electrode shown in FIG.98 showing the integrated slider switch, according to one aspect of thepresent disclosure.

FIGS. 100-102 illustrate various flexible circuit electrodeconfigurations with a controlled switching area to control variousswitching modes enabling a flexible circuit to be turned on and off indifferent areas, according to one aspect of the present disclosure,where:

FIG. 100 is a planar view of a flexible circuit electrode configured toenable inner and outer portions of the electrode to be controlledseparately and independently, according to one aspect of the presentdisclosure;

FIG. 101 is a planar view of a flexible circuit electrode configured toenable separate and independent control of the distal tip of theelectrode, according to one aspect of the present disclosure; and

FIG. 102 is a section view of a flexible circuit electrode configured toenable separate and independent control of the outer edges of theelectrode, according to one aspect of the present disclosure.

FIGS. 103-113 illustrates techniques for switching and controlling aradio frequency (RF) flexible circuit electrode, according to variousaspects of the present disclosure, where:

FIG. 103 is a diagram illustrating the components and interconnectionsof a system of an electrosurgical instrument for switching andcontrolling a radio frequency (RF) flexible circuit electrode, accordingto one aspect of the present disclosure;

FIG. 104 is diagram of the system for switching and controlling a radiofrequency (RF) flexible circuit electrode shown in FIG. 103 where anapplication specific integrated circuit (ASIC) is employed for thecontrol circuit, according to one aspect of the present disclosure;

FIG. 105 is an electrical schematic of the system for switching andcontrolling a radio frequency (RF) flexible circuit electrode shown inFIGS. 103 and 104, according to one aspect of the present disclosure;

FIG. 106 is a diagram of a serial communication circuit that may beemployed by the system shown in FIG. 102, according to one aspect of thepresent disclosure;

FIG. 107 is a waveform generator circuit configured to generate up to 4synchronous arbitrary digital waveforms that may be employed by thesystem shown in FIG. 102, according to one aspect of the presentdisclosure;

FIG. 108 is a stepper motor control circuit configured to drive astepper motor that may be employed by the system shown in FIG. 102,according to one aspect of the present disclosure;

FIG. 109 is a quadrature encoder for sensing the position of a rotatingdisk that may be employed by the system shown in FIG. 102, according toone aspect of the present disclosure;

FIG. 110 is a schematic diagram of the quadrature encoder shown in FIG.109, according to the present disclosure;

FIG. 111 is a section view of a flexible circuit electrode comprising asensing layer disposed below a polyimide layer, which is disposed belowan electrically conductive layer, according to one aspect of the presentdisclosure;

FIG. 112 is a plan view of a segmented flexible circuit electrodecomprising four segments, according to one aspect of the presentdisclosure; and

FIG. 113 is a logic diagram for controlling a segmented flexible circuitelectrode that may be employed by the system shown in FIGS. 103 and 104,according to one aspect of the present disclosure.

FIGS. 114-118 illustrate a mechanical temperature switch embedded in amulti layer flexible circuit electrode to implement flexible circuitswitching electrodes based on the bimetal temperature principle,according to one aspect of the present disclosure, where:

FIG. 114 is a cross section view of a multilayer flexible circuitelectrode comprising a mechanical switch in the form of a dome disposedon the lowest layer of the multilayer flexible circuit electrode in anon-contact state, according to one aspect of the present disclosure;

FIG. 115 is a lower plan view of the multilayer flexible circuitelectrode shown in FIG. 114, according to one aspect of the presentdisclosure;

FIG. 116 is an upper plan view of the multilayer flexible circuitelectrode shown in FIG. 114, according to one aspect of the presentdisclosure;

FIG. 117 is a cross section view of the multilayer flexible circuitelectrode showing the dome formed on the lowest layer of the multilayerflexible circuit electrode in an electrical contact state, according toone aspect of the present disclosure; and

FIG. 118 is a cross section view of a multilayer flexible circuitelectrode comprising a mechanical switch in the form of a springdisposed on the lowest layer of the multilayer flexible circuitelectrode in a non-contact state, according to one aspect of the presentdisclosure;

FIGS. 119-121 illustrate a segmented flexible circuit electrodeincluding a sensor configured to provide feedback to a motorized knifecontrol circuit for controlling the position of the motorized knife,according to one aspect of the present disclosure, where,

FIG. 119 illustrates the segmented flexible circuit electrode where onlythe proximal electrode segment is activated, according to one aspect ofthe present disclosure;

FIG. 120 illustrates a segmented flexible circuit electrode where onlythe intermediate electrode segment is activated, according to one aspectof the present disclosure; and

FIG. 121 illustrates a segmented flexible circuit electrode where onlythe distal electrode segment is activated, according to one aspect ofthe present disclosure.

FIG. 122 illustrates a multi-zone segmented flexible circuit electrodeconfigured to output different algorithms for each zone and treat tissuein each zone independently, according to one aspect of the presentdisclosure.

FIGS. 123-124 illustrate a technique for implementing a multiplexer withflexible electronic circuits to provide improved control methods,according to one aspect of the present disclosure, where:

FIG. 123 illustrates a two line multiplexer implemented with flexibleelectronic circuits, according to one aspect of the present disclosure;and

FIG. 124 illustrates a jaw configuration with independently actuatableelectrodes, according to one aspect of the present disclosure.

FIG. 125 illustrates a flexible circuit segmented electrode comprisingan inner electrode and an outer electrode that have different thermalconductivity properties for altering tissue effects, according to oneaspect of the present disclosure.

FIGS. 126-130 illustrates an integrated thin flexible circuit electrodeshown in FIG. 126 comprising a pressure sensor integrated with theflexible circuit electrode, according to one aspect of the presentdisclosure, where:

FIG. 126 is a elevation section view of a thin and flexible circuitelectrode comprising a switching pressure sensor, according to oneaspect of the present disclosure;

FIG. 127 is a lower plan view of the flexible circuit electrode shown inFIG. 126 showing the pressure sensor, according to one aspect of thepresent disclosure;

FIG. 128 is a side view of the flexible circuit electrode shown in FIG.126 with an embedded pressure sensor, according to one aspect of thepresent disclosure;

FIG. 129 is a plan view of the flexible circuit electrode shown in FIG.126 with a tissue bundle present thereon, according to one aspect of thepresent disclosure; and

FIG. 130 is a plan view of the flexible circuit electrode shown in FIG.126 with a vessel present, according to one aspect of the presentdisclosure.

FIGS. 131-133 illustrate a flexible circuit electrode comprisingselective electrode zone activation employing piezoelectric pressuredetection, according to tone aspect of the present disclosure, where:

FIG. 131 illustrates a segmented flexible circuit electrode divided intothree activation segments, according to one aspect of the presentdisclosure;

FIG. 132 is a section view of the segmented flexible circuit electrodeshown in FIG. 131 showing an electrode, a circuit, a piezoelectricsensor, and a knife slot according to one aspect of the presentdisclosure; and

FIG. 133 schematically illustrates a load pressure from tissue beingapplied to electrode segments (sections 2-3) and a reaction pressureapplied to underlying ceramic piezoelectric sensors, according to oneaspect of the present disclosure.

FIGS. 134-136 illustrate an optical temperature sensor embedded in aflexible circuit electrode, according to one aspect of the presentdisclosure, where:

FIG. 134 is a plan view of an optical temperature sensor embedded in aflexible circuit electrode, according to one aspect of the presentdisclosure;

FIG. 135 is as section view of the optical temperature sensor embeddedin a flexible circuit electrode taken along section line 135-135 asshown in FIG. 134, according to one aspect of the present disclosure;and

FIG. 136 is a schematic of a bent fiber section curved with a radius ofcurvature R, according to one aspect of the present disclosure.

FIGS. 137-138 illustrate a flexible circuit bladder sensor for sensingpressure and temperature, according to one aspect of the presentdisclosure, where:

FIG. 137 is an exploded view of the flexible circuit bladder sensor,according to one aspect of the present disclosure;

FIG. 138 is an elevation view of the flexible circuit bladder sensorattached to a jaw member of an end effector, according to one aspect ofthe present disclosure; and

FIG. 138A is a section view of the pressure sensing integrated circuit,according to one aspect of the present disclosure.

FIGS. 139-140 illustrate a flexible circuit thermocouple sensor,according to one aspect of the present disclosure, where:

FIG. 139 is a schematic diagram of the flexible circuit thermocouplesensor, according to one aspect of the present disclosure; and

FIG. 140 is a section view of the flexible circuit thermocouple sensor,according to one aspect of the present disclosure.

FIGS. 141-142 illustrate a pulse-oximeter and/or an i-watch sensorintegrated in a flexible circuit electrode for identifying blood flow intissue located between the jaws prior to clamping and cutting, accordingto one aspect of the present disclosure, where:

FIG. 141 illustrates a system 3600 comprising an electrosurgicalinstrument 3602 coupled to a generator 3604, according to one aspect ofthe present disclosure; and

FIG. 142 is a detail view of the end effector shown in FIG. 141comprising a pulse-oximeter sensor integrated in the flexible circuitelectrodes, according to one aspect of the present disclosure.

FIGS. 143-147 illustrate electro optical sensors integrated with aflexible circuit for sensing tissue properties, according to one aspectof the present disclosure, where:

FIG. 143 illustrates an exploded view of an electro optical sensor forsensing of tissue properties integrated with a flexible circuitelectrode, according to one aspect of the present disclosure;

FIG. 144 is a plan view of the flexible circuit electrode comprising anelectro optical sensor for sensing of tissue properties shown in FIG.143 integrated in a via of the flexible circuit electrode 3702,according to one aspect of the present disclosure;

FIG. 145 is a section view of the electro optical sensor integrated in avia of a flexible circuit electrode for sensing of tissue properties,according to one aspect of the present disclosure;

FIG. 146 is an elevation view of an end effector with a flexible circuitelectrode comprising an electro optical sensor integrated therewith,according to one aspect of the present disclosure; and

FIG. 147 is a plan view of a flexible circuit electrode comprising aplurality of electro optical sensors integrated with, according to oneaspect of the present disclosure.

FIG. 148 illustrates a flexible circuit electrode comprising a vascularsensor comprising a LED and photodiode arrangement integrated therewithfor sensing vascularity, according to one aspect of the presentdisclosure.

FIGS. 149-150 illustrate a vascular tissue sensor integrated with anflexible circuit electrode, according to one aspect of the presentdisclosure, where:

FIG. 149 is an end effector comprising upper and lower jaw members and avascular tissue sensor integrated with a flexible circuit electrode,according to one aspect of the present disclosure; and

FIG. 150 is a schematic diagram of a sensor for mobile heart ratemonitoring, according to one aspect of the present disclosure.

FIGS. 151-157 illustrate various attachment techniques to connect anddisconnect flexible circuits to wiring on re-usable instrumentconnections, according to one aspect of the present disclosure, where:

FIG. 151 illustrates a flexible circuit termination comprising supportedfingers, according to one aspect of the present disclosure;

FIG. 152 illustrates a flexible circuit termination comprisingunsupported fingers, according to one aspect of the present disclosure;

FIG. 153 illustrates an example flexible circuit electrode with foursupported fingers exposed on the proximal end, according to one aspectof the present disclosure;

FIG. 154 is the frontside of a female electrical connector configures toreceive a flexible circuit electrode, according to one aspect of thepresent disclosure;

FIG. 155 illustrates the backside of the electrical connector shown inFIG. 154, according to one aspect of the present disclosure;

FIG. 156 is an internal section view of biased contacts connected tosupported finger shown in FIG. 153, according to one aspect of thepresent disclosure; and

FIG. 157 is a full flexible circuit electrode assembly comprising aflexible circuit electrode connected to a connector, according to oneaspect of the present disclosure.

FIGS. 158-164 illustrate flexible circuit electrode attachment featuresfor connection and mechanical attachment, according to one aspect of thepresent disclosure to processing circuits and energy sources, where:

FIG. 158 is a perspective view of a flexible circuit electrode withattachment/alignment features provided on a surface thereon, accordingto one aspect of the present disclosure;

FIG. 159 is a section elevation view of a lower jaw member with theflexible circuit electrode shown in FIG. 158 with attachment/alignmentfeatures shown in FIG. 158 prior to being disposed thereon, according toaspect of the present disclosure;

FIG. 160 is a section view of the lower jaw member shown in FIG. 159with the flexible circuit electrode with attachment/alignment featuresshown in FIG. 159 prior to being disposed thereon, according to aspectof the present disclosure;

FIG. 161 is a partial perspective view of the flexible circuit electrodeshown in FIG. 158 disposed on an insulative flexible substrate with asolder point for connecting an attachment/alignment feature shown inFIG. 158 to the flexible circuit electrode, according to one aspect ofthe present disclosure;

FIG. 162 is an exploded view of the flexible circuit electrode show inFIG. 158 with multiple attachment/alignment features shown removed fromthe flexible circuit electrode, according to aspect of the presentdisclosure;

FIG. 163 is an exploded view of lower a flexible circuit electrode witha single attachment/alignment feature shown removed from the flexiblecircuit electrode, according to aspect of the present disclosure; and

FIG. 164 is a perspective view of a flexible circuit electrodecomprising an attachment feature for a wire/cable connector, accordingto one aspect of the present disclosure.

FIGS. 165-173 illustrate a flexible circuit electrode includingalternate contacts for routing and wiring multiple electrode paths tomonopolar or bipolar instruments for spot coagulation, according to oneaspect of the present disclosure, where:

FIG. 165 is a perspective view of an end effector comprising an upperand lower jaw member comprising a flexible circuit electrode with adistal monopolar electrode and lateral bipolar electrodes, according toone aspect of the present disclosure;

FIG. 166 is a plan view of the flexible circuit electrode shown in FIG.165, according to one aspect of the present disclosure;

FIG. 167 is a detail section view of the proximal end of the flexiblecircuit electrode shown in FIG. 166 showing the electrically conductivetraces for the distal monopolar electrode and the lateral bipolarelectrodes, according to one aspect of the present disclosure;

FIG. 168 is a perspective view of a lower jaw member of a jaw assemblycomprising a fold over flexible circuit electrode, according to oneaspect of the present disclosure;

FIG. 169 is a detail view of the fold over flexible circuit electrodeshown in FIG. 166, according to one aspect of the present disclosure;

FIG. 170 is a perspective view of a rotating contact assembly disposedabout the outer surface of an inner tube of a shaft component of theelectrosurgical instrument, according to one aspect of the presentdisclosure;

FIG. 171 is a detail section view of electrical contact wiperselectrically and rotatably coupled to the plurality of rotating contactsof the rotating contact assembly disposed about the outer surface of theinner tube, according to one aspect of the present disclosure;

FIG. 172 is a perspective view of the rotating contact assembly,according to one aspect of the present disclosure; and

FIG. 173 is a perspective view of the rotating contact assemblycomprising an outer tube, an inner tube, and a plurality of rotatingcontacts formed on a flexible circuit electrode and disposed about theinner tube, according to one aspect of the present disclosure.

FIGS. 174-176 illustrate flexible circuit comprising a snap in electrodeassembly and grasping/gap setting elements at a distal end, the elementshaving various geometries to aid in grasping and setting the gap betweenthe upper jaw and the lower jaw members of a clamp jaw assembly, and aconnecting scheme to couple the snap in electrode assembly to the clampjaw assembly, according to one aspect of the present disclosure, where:

FIG. 174 is a perspective view of a flexible circuit comprising a snapin electrode assembly at a distal end and an edge connector thatcontains an identification card at a proximal end, according to oneaspect of the present disclosure;

FIG. 174A is a detail view of two types of elements, according tovarious aspects of the present disclosure;

FIG. 175 is a section view of the proximal end of the flexible circuittaken along section line 175-175, as shown in FIG. 174, showing a T-slotconfiguration for alignment of the flexible circuit with the shaft; and

FIG. 176 is an elevation view of a clamp jaw assembly showing the femaleend of an edge connector and snap fit feature for electrically andmechanically coupling the connector portion of the flexible circuitelectrode in to the clamp jaw assembly as shown in FIG. 174 to a controlcircuit and/or a generator, according to one aspect of the presentdisclosure.

FIGS. 177-178 illustrate an automatic electrode renewal system forflexible circuit electrodes, such as spools of flexible circuitelectrodes, according to one aspect of the present disclosure, where:

FIG. 177 is an elevation view of a clamp jaw assembly comprising anupper jaw element and a lower jaw element and a renewable flexiblecircuit electrode system for unwinding and advancing clean flexiblecircuit electrodes from a proximal end pair of upper and lower rollersand winding used flexible circuit electrodes about a distal end pair ofupper and lower spools in a distal direction, according to aspect of thepresent disclosure; and

FIG. 178 is an elevation view of the automatic electrode renewal systemshown in FIG. 177 comprising an electrical brush contact to electricallycouple to a flexible circuit electrode disposed about the lower rollerat the proximal end, according to one aspect of the present disclosure.

FIGS. 179-184 illustrate a flexible circuit comprising an electrode anda vibratory element to mitigate tissue sticking to the clamp jawmembers, according to one aspect of the present disclosure, where:

FIG. 179 is a section view of a piezoelectric bimorph transducerattached to a flexible circuit electrode, according to one aspect of thepresent disclosure;

FIG. 180 is a schematic illustration of the displacement of thepiezoelectric bimorph transducer shown in FIG. 179, where a first modeof deflection is shown in solid line and a second mode of deflection isshown in dashed line, according to one aspect of the present disclosure;

FIG. 181 is a section view of a clamp jaw assembly comprising upper andlower bimorph transducers located in respective upper and lower jawmembers, according to one aspect of the present disclosure;

FIG. 182 is a section view of the clamp jaw assembly shown in FIG. 181,where the bimorph transducers located in the respective upper and lowerjaw members are in the second mode of maximum deflection (FIG. 180),according to one aspect of the present disclosure;

FIG. 183 is a section view of the lower bimorph transducer located on alower jaw member of the clamp jaw assembly configured in sensor mode tomeasure the adhesion force “F” of tissue sticking to the lower jawmember, according to one aspect of the present disclosure; and

FIG. 184 is a logic flow diagram of a technique for operating a bimorphtransducer by switching between a force measuring bimorph sensor to adriving bimorph transducer resulting in vibrations proportional to theadhesion force, according to one aspect of the present disclosure.

FIGS. 185-186 illustrate a jaw member comprising a flexible circuitelectrode assembly comprising a vibratory element configured to vibrateto reduce tissue adhesion on an electrode or remove tissue adhered tothe electrode, according to one aspect of the present disclosure, where:

FIG. 185 is a plan view of a vibrating jaw member comprising a flexiblecircuit electrode assembly configured to vibrate to reduce tissueadhesion to the electrode or remove tissue adhered to the electrode,according to one aspect of the present disclosure; and

FIG. 186 is a section view of the vibrating jaw comprising a flexiblecircuit electrode shown in FIG. 186 taken along section 186-186,according to one aspect of the present disclosure;

FIG. 187 is a schematic diagram of a circuit configured to activate theflexible circuit electrode assembly (FIGS. 185-186) and thepiezoelectric element (FIG. 186) simultaneously, according to one aspectof the present disclosure.

FIGS. 188-189 illustrate a jaw member 4600 of clamp jaw assemblycomprising a flexible circuit 4602 comprising an inner electrode 4604for applying therapy to tissue and an outer electrode 4608 for sensing,powering accessory functions, and proximity detection among otherfunctions, according to one aspect of the present disclosure, where:

FIG. 188 is a perspective view of a jaw member comprising a flexiblecircuit comprising an inner electrode and an outer electrode, accordingto one aspect of the present disclosure; and

FIG. 189 is a detail view of the jaw member shown in FIG. 188, accordingto one aspect of the present disclosure.

FIGS. 190-192 illustrate a flexible circuit electrode assemblycomprising electrodes for tissue treatment and LEDs for illuminatingtissue, according to one aspect of the present disclosure, where:

FIG. 190 is an elevation view of a clamp jaw assembly comprising anupper jaw member and a lower jaw member comprising a flexible circuitelectrode assembly in the lower jaw member, according to one aspect ofthe present disclosure;

FIG. 191 is a plan view of the flexible circuit electrode assemblycomprising the electrode and the plurality of LEDs positioned around theperiphery of the lower jaw member, according to one aspect of thepresent disclosure; and

FIG. 192 is a section view of the flexible circuit electrode assemblytaken along section line 192-192 as shown in FIG. 191, according to oneaspect of the present disclosure.

FIGS. 193-194 illustrate a flexible circuit electrode assemblycomprising an electrode and an LED for signaling status, according toone aspect of the present disclosure, where:

FIG. 193 is a perspective view of a clamp jaw assembly comprising anupper jaw member and a lower jaw member and a flexible circuit electrodeassembly, according to one aspect of the present disclosure; and

FIG. 194 is a plan view of the flexible circuit electrode assembly 4904shown in FIG. 193, according to one aspect of the present disclosure.

FIGS. 195-196 illustrate a flexible circuit electrode assemblycomprising an optical sensing system comprising at least one lightemitting diode (LED) and photo sensor to provide an indication of tissuestatus and visualization of the surgical site, according to one aspect,where:

FIG. 195 is an elevation view of a clamp jaw assembly comprising anupper jaw member and a lower jaw member and a flexible circuit electrodeassembly, according to one aspect of the present disclosure; and

FIG. 196 is a logic diagram of operating the optical sensing systemdescribed in connection with FIG. 195, according to one aspect of thepresent disclosure.

FIG. 197 illustrates a flexible circuit electrode assembly comprising anelectrode and a light pipe, according to one aspect of the presentdisclosure.

FIG. 198 illustrates a flexible circuit electrode assembly comprising anelectrode and a light pipe, according to one aspect of the presentdisclosure.

FIGS. 199-208 illustrate a flexible circuit inductive sensorinductance-to-digital converter circuit and operation thereof, accordingto one aspect of the present disclosure, where:

FIG. 199 illustrate a proximity sensor system comprising an inductiveelement formed on a flexible circuit, according to one aspect;

FIG. 200 is a functional block diagram of the proximity sensor system,according to one aspect;

FIG. 201 is a simplified circuit model of the proximity sensor systemand a proximal metal target, according to one aspect of the presentdisclosure;

FIG. 202 is a simplified circuit model of a metal target modeled as Land R with circulating eddy currents, according to one aspect of thepresent disclosure;

FIG. 203 is a schematic diagram of a linear position sensing systemcomprising a flexible circuit inductive element and aninductance-to-digital converter circuit, according to one aspect of thepresent disclosure;

FIG. 204 is a graphical representation of the linear position sensingsystem shown in FIG. 203, according to one aspect of the presentdisclosure;

FIG. 205 is a schematic diagram of an angular position sensing systemcomprising a flexible circuit inductive element, according to one aspectof the present disclosure;

FIG. 206 is a graphical representation of the angular position sensingsystem shown in FIG. 203, according to one aspect of the presentdisclosure;

FIG. 207 is an upper layer layout of the flexible circuit inductiveelement and inductance-to-digital converter circuit; and

FIG. 208 is a lower layer layout of the flexible circuit inductiveelement and inductance-to-digital converter circuit.

FIGS. 209-210 illustrate examples of flexible circuit electrodes coatedwith ultraviolet (U.V.) cured paint insulation systems, according to oneaspect of the present disclosure, where:

FIG. 209 illustrates an electrical connection or joint of a flexiblecircuit electrode assembly in the process of being coated by electrospraying a dielectric material thereon, according to one aspect of thepresent disclosure.

FIG. 210 is an electrical schematic diagram of the electrospray process,according to one aspect of the present disclosure.

FIGS. 211-215 illustrate temperature sensor overmolded with a flexiblecircuit electrode assembly located in a jaw member to provide abiocompatible clamp jaw assembly, according to one aspect of the presentdisclosure, where:

FIG. 211 is a perspective view of a clamp jaw assembly configured for anelectrosurgical instrument tissue sealer comprising an embeddedtemperature sensor 5506, according to one aspect of the presentdisclosure;

FIG. 212 is a plan view of the flexible circuit electrode assemblycomprising an embedded temperature sensor overmolded therewith,according to pone aspect of the present disclosure;

FIG. 213 is a perspective view from the proximal end of the flexiblecircuit electrode assembly with a temperature sensor overmoldedtherewith, according to one aspect of the present disclosure;

FIG. 214 is a section view of the flexible circuit electrode assemblywith a temperature sensor overmolded therewith taken along section line214-214 as shown in FIG. 213, according to one aspect of the presentdisclosure; and

FIG. 215 is a section view of the flexible circuit electrode assemblywith a temperature sensor overmolded therewith taken along section line215-215 as shown in FIG. 213, according to one aspect of the presentdisclosure.

FIG. 216 illustrates a flexible circuit electrode assembly comprisingdual electrode heater elements, according to one aspect of the presentdisclosure

FIGS. 217-219 illustrate flexible circuit electrode assembliescomprising electric knife and cooling cells, such as superconductingheat and/or MEMS cooling cells, according to one aspect of the presentdisclosure, where:

FIGS. 217-219 illustrate a process of sealing, cooling, and cuttingtissue while cooling, according to one aspect of the present disclosure.

FIG. 217 is a section view of a clamp jaw assembly in the process ofperforming a first step of sealing tissue disposed in the clamp jawassembly, according to one aspect of the present disclosure;

FIG. 218 is a section view of the clamp jaw assembly shown in FIG. 217in the process of performing a second step of cooling the tissuedisposed in the clamp jaw assembly, according to one aspect of thepresent disclosure; and

FIG. 219 is a section view of the clamp jaw assembly 5700 shown in FIG.217 in the process of performing a third step of cooling and cutting thetissue disposed in the clamp jaw assembly, according to one aspect ofthe present disclosure.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof. In the drawings,similar symbols and reference characters typically identify similarcomponents throughout the several views, unless context dictatesotherwise. The illustrative aspects described in the detaileddescription, drawings, and claims are not meant to be limiting. Otheraspects may be utilized, and other changes may be made, withoutdeparting from the scope of the subject matter presented here.

The following description of certain examples of the technology shouldnot be used to limit its scope. Other examples, features, aspects,aspects, and advantages of the technology will become apparent to thoseskilled in the art from the following description, which is by way ofillustration, one of the best modes contemplated for carrying out thetechnology. As will be realized, the technology described herein iscapable of other different and obvious aspects, all without departingfrom the technology. Accordingly, the drawings and descriptions shouldbe regarded as illustrative in nature and not restrictive.

It is further understood that any one or more of the teachings,expressions, aspects, examples, etc. described herein may be combinedwith any one or more of the other teachings, expressions, aspects,examples, etc. that are described herein. The following-describedteachings, expressions, aspects, examples, etc. should therefore not beviewed in isolation relative to each other. Various suitable ways inwhich the teachings herein may be combined will be readily apparent tothose of ordinary skill in the art in view of the teachings herein. Suchmodifications and variations are intended to be included within thescope of the claims.

Also, in the following description, it is to be understood that termssuch as front, back, inside, outside, upper, lower and the like arewords of convenience and are not to be construed as limiting terms.Terminology used herein is not meant to be limiting insofar as devicesdescribed herein, or portions thereof, may be attached or utilized inother orientations. The various aspects will be described in more detailwith reference to the drawings. Throughout this disclosure, the term“proximal” is used to describe the side of a component, e.g., a shaft, ahandle assembly, etc., closer to a user operating the surgicalinstrument, e.g., a surgeon, and the term “distal” is used to describethe side of the component further from the user operating the surgicalinstrument.

Aspects of the present disclosure are presented for a single surgicalinstrument configured for grasping tissue, performing sealing proceduresusing electrical or ultrasonic energy. An end effector of the surgicalinstrument may include multiple members arranged in variousconfigurations to collectively perform the aforementioned functions. Asused herein, an end effector may be referred to as a jaw assembly orclamp jaw assembly comprising an upper jaw member and a lower jaw memberwhere the upper jaw member is movable relative to the lower jaw member.In some aspects one or both jaw members are movable relative to eachother.

In some aspects, an end effector of a surgical instrument includes apair of jaws for grasping and applying electrical energy to tissue atthe surgical site. In some aspects, an end effector of a surgicalinstrument includes an ultrasonic member. The ultrasonic member may beimplemented in various different shapes, such as in a spoon shape, ahook shape, a wedge shape, or in a shape configured to grab or grasptissue. The ultrasonic member may be configured to deliver ultrasonicenergy through being vibrated at an ultrasonic frequency. In someaspects, the ultrasonic member may be retracted into a closure tube toallow for focused use of one or the other members.

In some aspects, any of the mentioned examples also may be configured toarticulate along at least one axis through various means, including, forexample, a series of joints, one or more hinges or flexure bearings, andone or more cam or pulley systems. Other various features may includecameras or lights coupled to one or more of the members of the endeffector, and various energy options for the surgical instrument. Thetype of energy applied at the surgical site may take various forms andincludes, without limitation, monopolar and/or bipolar radio frequency(RF) energy, microwave energy, reversible and/or irreversibleelectroporation energy, and/or ultrasonic energy, or any combinationthereof.

Various features described herein may be incorporated in electrosurgicaldevices for applying electrical energy to tissue in order to treatand/or destroy the tissue are also finding increasingly widespreadapplications in surgical procedures. An electrosurgical instrumenttypically includes a hand piece, an instrument having a distally-mountedend effector (e.g., one or more electrodes). The end effector can bepositioned against the tissue such that electrical current is introducedinto the tissue. Electrosurgical instrument can be configured forbipolar or monopolar RF energy operation, and/or microwave energy,reversible and/or irreversible electroporation energy, and/or ultrasonicenergy, or any combination thereof. During bipolar RF operation,electrical current is introduced into and returned from the tissue byactive and return electrodes, respectively, of the end effector. Duringmonopolar RF operation, current is introduced into the tissue by anactive electrode of the end effector and returned through a returnelectrode (e.g., a grounding pad) separately located on a patient'sbody. Heat generated by the current flowing through the tissue may formhemostatic seals within the tissue and/or between tissues and thus maybe particularly useful for sealing blood vessels, for example. The endeffector of an electrosurgical device also may include a cutting memberthat is movable relative to the tissue and the electrodes to transectthe tissue. Reversible and/or irreversible electroporation energy may beapplied through the end effector in a similar manner. In instrumentscomprising an ultrasonic member, electrical current may be conductedthrough the ultrasonic member.

Electrical energy applied by an electrosurgical device can betransmitted to the instrument by a generator in communication with thehand piece. Electrical energy applied by an electrosurgical device canbe transmitted to the instrument by a generator in communication withthe hand piece. The electrical energy may be in the form of RF energythat may be in a frequency range described in EN60601-2-2:2009+A11:2011, Definition 201.3.218—HIGH FREQUENCY. Forexample, the frequencies in monopolar RF applications are typicallyrestricted to less than 5 MHz. However, in bipolar RF applications, thefrequency can be almost anything. Frequencies above 200 kHz can betypically used for MONOPOLAR applications in order to avoid the unwantedstimulation of nerves and muscles which would result from the use of lowfrequency current. Lower frequencies may be used for BIPOLAR techniquesif the RISK ANALYSIS shows the possibility of neuromuscular stimulationhas been mitigated to an acceptable level. Normally, frequencies above 5MHz are not used in order to minimize the problems associated with HIGHFREQUENCY LEAKAGE CURRENTS. However, higher frequencies may be used inthe case of BIPOLAR techniques. It is generally recognized that 10 mA isthe lower threshold of thermal effects on tissue.

In application, an electrosurgical device can transmit low frequency RFenergy through tissue, which causes ionic agitation, or friction, ineffect resistive heating, thereby increasing the temperature of thetissue. Because a sharp boundary is created between the affected tissueand the surrounding tissue, surgeons can operate with a high level ofprecision and control, without sacrificing un-targeted adjacent tissue.The low operating temperatures of RF energy is useful for removing,shrinking, or sculpting soft tissue while simultaneously sealing bloodvessels. RF energy works particularly well on connective tissue, whichis primarily comprised of collagen and shrinks when contacted by heat.

FIG. 1A shows an electrosurgical instrument 2 in electricalcommunication with a generator 21, according to one aspect of thepresent disclosure. The surgical instrument 2 is configurable with aflexible circuit 3 according to various aspects. The surgical instrument2 comprises an elongate member 4, such as a shaft, having a proximalportion 9 coupled to a handle assembly 7. A distal portion 12 of theelongate member 4 comprises an end effector 14 (see FIG. 1B) coupled toa distal end of the shaft 10. In some aspects, the end effector 14comprises a first jaw 15 a and a second jaw 15 b, each having an outerportion or surface 16 a, 16 b. At least one of the first jaw 15 a andthe second jaw 15 b is rotatably movable relative to the other along apath shown by arrow J to transition the first and second jaws 15 a, 15 bbetween open and closed positions. In operation, the first and secondjaws 15 a, 15 b may be transitioned from the open position to a closedposition to capture tissue therebetween. Captured tissue may contact oneor more working portions of the jaw set, indicated generally as 17 a, 17b, configured to apply energy to treat target tissue located at or nearthe end effector 14. The type of energy may take various forms andincludes, without limitation, monopolar and/or bipolar radio frequency(RF) energy, microwave energy, reversible and/or irreversibleelectroporation energy, and/or ultrasonic energy, or any combinationthereof.

The handle assembly 7 comprises a housing 18 defining a grip 19. Invarious aspects, the handle includes one or more control interfaces 20a-c, e.g., a button or switch 20 a, rotation knob 20 b rotatable alongarrow R, and a trigger 20 c movable relative to the grip 19 along arrowT, configured to provide operation instructions to the end effector 13.Multiple buttons, knobs, or triggers described also may be included aspart of the housing 18 in order to manipulate one or more of thefunctioning members at the end effector 14. In some aspects, the handleassembly 7 is further configured to electrically couple to a generator21 to supply the surgical instrument 2 with energy. While the generator21 is illustrated as generally coupled to the handle assembly 7, e.g.,with a cord, it is to be understood that in some aspects the generator21 may be positioned within the elongate member 4. For example, in oneaspect, the generator 21 comprises one or more direct current batteriespositioned in the handle assembly 7, shaft 10, or a portion thereof.

FIG. 1C illustrates an example of a generator 21 for delivering multipleenergy modalities to a surgical instrument. As noted above, at least onegenerator output can deliver multiple energy modalities (e.g.,ultrasonic, bipolar or monopolar RF, irreversible and/or reversibleelectroporation, and/or microwave energy, among others) through a singleport and these signals can be delivered separately or simultaneously tothe end effector to treat tissue. FIG. 10 illustrates an example of agenerator 21 for delivering multiple energy modalities to a surgicalinstrument. The generator 21 comprises a processor 22 coupled to awaveform generator 24. The processor 22 and waveform generator 24 areconfigured to generate a variety of signal waveforms based oninformation stored in a memory coupled to the processor 22, not shownfor clarity of disclosure. The digitally information associated with awaveform is provided to the waveform generator 24 which includes one ormore digital-to-analog (DAC) converters to convert the digital inputinto an analog output. The analog output is fed to an amplifier 26 forsignal conditioning and amplification. The conditioned and amplifiedoutput of the amplifier 26 is coupled to a power transformer 28. Thesignals are coupled across the power transformer 28 to the secondaryside, which is in the patient isolation side. A first signal of a firstenergy modality is provided to the surgical instrument between theterminals labeled ENERGY₁ and RETURN₁. A second signal of a secondenergy modality is coupled across a capacitor 30 and is provided to thesurgical instrument between the terminals labeled ENERGY_(n) andRETURN_(n). The subscript n is used to indicate that up to nENERGY/RETURN terminals may be provided, where n is a positive integergreater than 1. As an example, the first energy modality may beultrasonic energy and the second energy modality may be RF energy.Nevertheless, in addition to ultrasonic and bipolar or monopolar RFenergy modalities, other energy modalities include irreversible and/orreversible electroporation and/or microwave energy, among others. Also,although the example illustrated in FIG. 10 shows separate return pathsRETURN₁ and RETURN_(n), it will be appreciated that at least one commonreturn path may be provided for two or more energy modalities.

A voltage sensing circuit 32 is coupled across the terminals labeledENERGY₁ and RETURN₁ to measure the output voltage. A current sensingcircuit 34 is disposed in series with the RETURN₁ leg of the secondaryside of the power transformer 28 as shown to measure the output current.The outputs of the voltage sensing circuit 32 is provided to anisolation transformer and analog-to-digital converter (ADC) 36 and theoutput of the current sensing circuit 34 is provided to anotherisolation transformer and ADC 38. The digital version of the outputvoltage and output current are fed back to the processor 22. The outputvoltage and output current information can be employed to adjust theoutput voltage and current provided to the instrument and to computeoutput impedance, among other parameters. Input/output communicationsbetween the processor 22 and patient isolated circuits is providedthrough an interface circuit 40. It will be appreciated that a similarvoltage sensing circuit may be provided across the ENERGY_(n) andRETURN_(n) terminals and a similar current sensing circuit may bedisposed in series with the RETURN_(n) leg.

As shown in FIG. 10, the generator 21 comprises at least one output portcan include a power transformer 28 with a single output and withmultiple taps to provide power in the form of one or more energymodalities, such as ultrasonic, bipolar or monopolar RF, irreversibleand/or reversible electroporation, and/or microwave energy, amongothers, for example, to the end effector depending on the type oftreatment of tissue being performed. For example, the generator 21 candeliver energy with higher voltage and lower current to drive anultrasonic transducer, with lower voltage and higher current to drive RFelectrodes for sealing tissue, or with a coagulation waveform for spotcoagulation using either monopolar or bipolar RF electrosurgicalelectrodes. The output waveform from the generator 21 can be steered,switched, or filtered to provide the frequency to the end effector ofthe surgical instrument. The connection of a transducer to the generator21 output would be preferably located between the output labeled ENERGY1and RETURN₁ as shown in FIG. 10. In one example, a connection of RFbipolar electrodes to the generator 21 output would be preferablylocated between the output labeled ENERGY_(n) and RETURN_(n). In thecase of monopolar output, the preferred connections would be activeelectrode (e.g., pencil or other probe) to the ENERGY_(n) output and asuitable return pad connected to the RETURN_(n) output.

The following descriptions and related figures provide examples of moredetailed designs of the end effector 14, including one or more membersfor grasping and applying sealing energy, and one or more members with afluid path for suction and irrigation. The following are merelyexamples, and it may be apparent to those with skill in the art how thevarious examples may be combined or interchanged to be included invarious other aspects, and aspects are not so limited.

I. Flexible Circuit Electrode Configurations A. Bipolar Flexible CircuitElectrode Assembly

FIG. 2 illustrates a bipolar flexible circuit electrode assembly 50 thatutilizes the flexible nature of flexible circuit electrode manufacturingprocess to incorporate a variety of lead 52 lengths and active/passivecomponents in the electrode circuit, according to one aspect of thepresent disclosure. The bipolar flexible circuit electrode assembly 50comprises an upper jaw flexible circuit electrode 54 a and a lower jawflexible circuit electrode 54 b. A flexure bearing 58 connects the upperand lower jaw electrodes 54 a, 54 b. As used herein, the flexure bearingis made from the same material as the two flexible circuit electrodes itconnects, and may be referred to as a living hinge or living bearing.The upper and lower jaw flexible electrodes 54 a, 54 b are configured tomount to a clamp jaw assembly, such as, for example, the end effector 14shown in FIG. 1C, of the electrosurgical device such as, for example,the surgical instrument 2 shown in FIG. 1A. The upper and lower jawflexible electrodes 54 a, 54 b are electrically coupled to an generator21 at the handle assembly 7 of the electrosurgical instrument 2, allshown in FIG. 1A. The lead 52 is disposed within the shaft 10 of theelectrosurgical instrument 2, as shown in FIGS. 1A, 1B. The lower jawelectrode 54 b comprises an electrically insulative layer 55 defining aplurality of electrically insulative elements 56 to prevent the upperand lower jaw electrodes 54 a, 54 b from shorting when the jaws are in aclosed configuration. The electrically insulative elements 56 define agap between the upper and lower jaw electrodes 54 a, 54 b when they arein a closed configuration and also improve tissue grasping between thejaw electrodes 54 a, 54 b.

In one aspect, the electrically insulative elements 56 can be providedon the upper jaw electrode 54 a and in other aspects the electricallyinsulative elements 56 can be provided on both the upper and lower jawelectrodes 54 a, 54 b. The electrically insulative elements 56 can beformed of a dielectric material which can be printed on the flexiblecircuit electrodes 54 a, 54 b as described in further detail herein. Inyet another aspect, the insulative layer 55 may be configured as anelectrically insulative cover that further defines the electricallyconductive lower jaw electrode 54 b and can act as a spacer element. Inone aspect, the electrically insulative elements 56 may comprise anonstick coating or may be formed of a nonstick material such aspolytetrafluoroethylene (PTFE), which is a synthetic fluoropolymer oftetrafluoroethylene that has numerous applications. The best known brandname of PTFE-based formulas is TEFLON by DuPont Co., for example. In oneaspect, the electrically insulative elements 56 may be formed of adielectric material.

In one aspect, the electrically insulative layer 55 may be formed bybonding a dielectric cover film on the tissue contacting surface of theflexible circuit electrodes 54 a, 54 b. In one aspect, the electricallyinsulative elements 56 may be formed by etching the dielectric coverfilm bonded to the tissue contacting surface of the electrode 54 a, 54b. In one aspect, at least one of the electrically insulative elements56 may be configured as a spacer to provide a predetermined gap betweenupper and lower electrodes.

As used throughout this description, the term element is used to refer apiece of material used to create or maintain a space between two things,such as jaw members of an end effector. The pacers may be electricallyconductive or nonconductive and in various aspects are formed of adielectric material. In one aspect, the elements can be made of aPositive Thermal Coefficient (PTC) ceramic, e.g., barium titanate orlead titanate composites. The elements can alternatively be made ofexotic materials, including platinum, molybdenum disilicide, and siliconcarbide. These are just a few examples, which are not meant to belimiting. In an electrically conductive configuration, the elements maybe employed to set a uniform or non-uniform predetermined gap betweentissue contacting surfaces of the upper and lower jaw members. In anelectrically nonconductive configuration, the elements may be employedto set a uniform or non-uniform predetermined gap between tissuecontacting surfaces of the upper and lower jaw members and prevent theelectrodes in the upper and lower jaw members from electricallyshorting.

FIG. 3 illustrates a detail view of a bipolar flexible circuit electrodeassembly 60 comprising a short lead 62 length, according to one aspectof the present disclosure. The bipolar flexible circuit electrodeassembly 60 comprises an upper jaw flexible circuit electrode 64 a and alower jaw flexible circuit electrode 64 b. A flexure bearing 68 connectsthe upper and lower jaw electrodes 64 a, 64 b. The upper and lower jawflexible electrodes 64 a, 64 b are configured to mount to a clamp jawassembly, such as, for example, the end effector 14 shown in FIG. 1C, ofthe electrosurgical device such as, for example, the surgical instrument2 shown in FIG. 1A. The upper and lower jaw flexible electrodes 64 a, 64b are electrically coupled to a generator 21 at the handle assembly 7 ofthe electrosurgical instrument 2, all shown in FIG. 1A. The short lead62 provides for replaceable electrodes 64 a, 64 b or a replaceable jawassembly of the end effector 14.

The lower jaw electrode 64 b comprises an electrically insulative layer65 defining a plurality of electrically insulative elements 66 toprevent the upper and lower jaw electrodes 64 a, 64 b from shorting whenthe jaws are in a closed configuration. The electrically insulativeelements 66 also define a gap between the upper and lower jaw electrodes64 a, 64 b when they are in a closed configuration and also improvetissue grasping between the jaw electrodes 64 a, 64 b. In one aspect,the electrically insulative elements 66 can be provided on the upper jawelectrode 64 a and in other aspects the electrically insulative elements66 can be provided on both the upper and lower jaw electrodes 64 a, 64b. The electrically insulative elements 66 can be formed of a dielectricmaterial which can be printed on the flexible circuit electrodes 64 a,64 b as described in further detail herein. In yet another aspect, theelectrically insulative layer 65 may be configured as an electricallyinsulative cover that further defines the electrically conductive lowerjaw electrode 64 b and can act as a spacer element.

The electrically insulative element 66 may be defined by theelectrically insulative layer 65 and can be configured as anelectrically insulative barrier between the jaw electrodes, provide apredetermined gap between the jaw electrodes, and/or assist tissuegrasping between the jaw electrodes. In one aspect, the electricallyinsulative elements 66 may comprise a nonstick coating or may be formedof a nonstick material such as TEFLON to prevent tissue from stickingthereto. In one aspect, the electrically insulative elements 66 may beformed of a dielectric material.

In one aspect, the electrically insulative layer 65 may be formed bybonding a dielectric cover film on the tissue contacting surface of theflexible circuit electrodes 64 a, 64 b. In one aspect, the electricallyinsulative elements 66 may be formed by etching the dielectric coverfilm bonded to the tissue contacting surface of the electrode 64 a, 64b. In one aspect, at least one of the electrically insulative elements66 may be configured as a spacer to provide a predetermined gap betweenupper and lower electrodes.

With reference now to FIGS. 2 and 3, in various aspects the bipolarflexible circuit electrode assemblies 50, 60 utilize the flexible natureof the flexible circuit electrode manufacturing process to incorporate avariety of lead lengths and active/passive components can be provided inthe electrode circuit. The bipolar flexible circuit electrode assemblies50, 60 can be configured in a variety of ways. For example, as shown inFIG. 2, the length of the lead 52 may be, to enable moving theelectrical termination point to the handle assembly 7 (FIG. 1A),reducing part count, electrical connection points and enabling theinclusion of additional active components such as switches, electricallyerasable programmable read only memory (EEPROM), etc., intimatelyassociated with the electrodes. Alternatively, as shown in FIG. 3, thelength of the short lead 62 can be short as shown in FIG. 3, i.e., nearthe flexure bearing 68 connecting the upper and lower jaw electrodes 64a, 64 b, which can enable replaceable electrodes 64 a, 64 b or jaws.

B. Bipolar Flexible Circuit Electrode Assembly Including Extended Leads

FIGS. 4-9 illustrate a flexible circuit electrode 100 comprising anextended lead 102, according to one aspect of the present disclosure.FIG. 4 is a perspective view of a flexible circuit electrode 100comprising an extended lead 102, according to one aspect of the presentdisclosure.

FIG. 5 is a plan view of the electrically conductive element 104 side ofthe flexible circuit electrode 100 shown in FIG. 4, according to oneaspect of the present disclosure. FIG. 6 is a plan view of theelectrically insulative element 110 side of the flexible circuitelectrode 100 shown in FIG. 5, according to one aspect of the presentdisclosure.

FIG. 7 is a side elevation view of the flexible circuit electrode 100shown in FIG. 4, according to one aspect of the present disclosure. FIG.8 is an elevation view of the flexible circuit electrode 100 shown inFIG. 4 taken from a distal end 112, according to one aspect of thepresent disclosure. FIG. 9 is an elevation view of the flexible circuitelectrode shown in FIG. 4 taken from a proximal end 114, according toone aspect of the present disclosure.

With reference now to FIGS. 4-9, the flexible circuit electrode 100comprises a lead 102 for connecting the electrode 100 to an energysource, such, for example, a radio frequency (RF) generator that outputsenough power to seal tissue. The lead 102 enables the electrode 100 tobe connected to the energy source at the handle portion of theelectrosurgical device. The electrode 100 comprises a jaw member portion116 that can be attached either to the upper jaw member, the lower jawmember, or both, of a clamp jaw assembly of the electrosurgicalinstrument. The jaw member portion 116 comprises at least oneelectrically conductive element 104 and a knife slot 108. The knifeportion of the electrosurgical instrument 2 (FIG. 1A) is slidablymovable within the knife slot 108 to cut the tissue after it has beensealed using electrosurgical energy.

In one aspect, an electrically insulative layer 105 may be provided onthe at least one electrically conductive element 104 to preventelectrically shorting the jaw member electrodes when they are in aclosed configuration. In another aspect, the electrically insulativelayer 105 defines at least one electrically insulative element 106 toestablish a predetermined gap between the jaw electrodes of a bipolarelectrosurgical instrument. In yet another aspect, the electricallyinsulative layer 105 may be configured as an electrically insulativecover that further defines the electrically conductive element 104 andcan act as a spacer. The electrically insulative element 106 may bedefined by the electrically insulative layer 105 and can be configuredas an electrically insulative barrier between the jaw electrodes,provide a predetermined gap between the jaw electrodes, and/or assisttissue grasping between the jaw electrodes. In one aspect, theelectrically insulative elements 106 may comprise a nonstick coating ormay be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 106 may be formed of a dielectric material.

In one aspect, the electrically insulative layer 105 may be formed bybonding a dielectric cover film on the electrically conductive element104. In one aspect, at least one of the electrically insulative elements106 may be formed by etching the dielectric cover film bonded to theelectrically conductive element 104. In one aspect, at least one of theelectrically insulative elements 106 may be configured as a spacer toprovide a predetermined gap between upper and lower electrodes.

The electrically conductive element 104 comprises electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. In one aspect, theelectrically insulative layer 105 further defines the at least oneelectrically conductive element 104. One or more than one of theelectrically conductive elements 104 may be configured and arranged todefine a conductive electrode.

The jaw member portion 116 of the flexible circuit electrode 100 definesa knife slot 108 that extends along a length of the jaw member portion116. Although generally speaking the knife slot 108 is laterallycentered, this is not necessarily always the case, and in other aspects,the knife slot 108 may be laterally offset from center.

The electrically insulative element 110 portion of the electricallyconductive element 104 of the flexible circuit electrode 100 is formedof electrically insulative material such as a polymer and morespecifically can be a polyimide, polyester, fluorocarbon, or anypolymeric material, or any combinations thereof. The electricallyinsulative element 110 of the electrically conductive element 104 isgenerally attached to the tissue contacting side of the upper or lowerjaw members of the clamp jaw assembly.

The flexible circuit electrode 100 can be mass produced for a bipolarmedical device, generally referred to as an electrosurgical device. Aflexible electrically conductive sheet (e.g., Cu) is bonded to anelectrically insulative backing sheet (e.g., polyimide backing) and theelectrically elements 106 are printed at two or more locations on theelectrically conductive element 104 of the electrode 100. The elements106 serve to prevent the electrode 100 from shorting within the opposingjaws, create a defined gap between the jaws, and/or assist tissuegrasping. After the elements 106 are printed on the electricallyconductive element 104 of the electrically conductive sheet.

In one aspect, the electrode 100 can be produced by laminating themetallic sheet to an electrically insulative film made of polyimide,polyester, fluorocarbon, or any polymeric material, or any combinationsthereof. The electrically insulative layer 105 as well as the elements106 may be screen printed on the conductive face of the electricallyconductive element 104 of the electrode 100. The shape of the electrode100 is formed by screen printing a protective barrier to the metallicfilm. This protective barrier allows the shape of the electrode 100 tobe formed by photoetching away the remaining material which does notmake up the final shape of the electrode 100. Finally the individualelectrode 100 is die-cut out leaving an electrode subassembly that canbe bonded to the jaws.

The electrically insulative element 110 can have an adhesive or abraze-able surface on the back side to attach the flexible circuitelectrode 100 to the lower or upper jaw of the end effector depending onthe jaw construction of the surgical instrument.

The various types of flexible circuit electrodes described in connectionwith FIGS. 2-66 can be manufactured in a manner similar to thatdescribed in the preceding paragraphs and for conciseness and clarity ofdisclosure will not be repeated in the description of such figures.Furthermore, a detailed process of manufacturing flexible circuitelectrodes is discussed in connection with FIGS. 73-81. The descriptionnow turns to another type of flexible circuit electrode comprising adielectric layer, which in one aspect comprises at least one nonstickelement and in a further aspect defines an annular configuration.

Further, any of the electrodes described in connection with FIGS. 2-66,may be formed of the following materials having the indicatedthicknesses. Potential materials and combination of materials for theelectrically conductive portion of the electrodes include copper, goldplated copper, silver, platinum, stainless steel, aluminum, or anysuitable electrically conductive biocompatible material, for example,among other electrically conductive metals and/or alloys. In oneexample, the flexible circuit electrode as described herein can includean electrically conductive metal layer (e.g., copper, gold platedcopper, silver, platinum, stainless steel, aluminum, or any suitableelectrically conductive biocompatible material, for example, among otherelectrically conductive metals and/or alloys), an electricallyinsulative film (e.g., polyimide, polyester, fluorocarbon, or anypolymeric material, or any combinations thereof) bonded to theelectrically conductive metal layer, and an adhesive used to bond theelectrically conductive metal layer to the electrically insulative film.

In one example, the flexible circuit electrode 100 comprises anacrylic-based copper clad laminate known under the trade name PyraluxLF9250 supplied by DuPont, the copper clad laminate comprising acoverlay, a bondply, and a sheet adhesive. A coverlay is a materiallaminated to the outside layers of the flexible circuit to insulate thecopper conductor and a bondply is an unreinforced, thermoset based thinfilm available in various thicknesses adhesive system intended for usein high performance, high reliability multi-layer flexible circuitconstructions. In one aspect, the components of the flexible circuitelectrode 100 may comprise a copper layer having a thickness of˜0.0028″, a polyimide film layer having a thickness of ˜0.005″, and anadhesive layer having a thickness of ˜0.001″ for a total thickness of˜0.0088″. In another example, the flexible circuit electrode 100comprises an acrylic-based copper clad laminate known under the tradename Pyralux LF9230 supplied by DuPont, the copper clad laminatecomprising a coverlay, a bondply, and a sheet adhesive. In one aspect,the components of the flexible circuit electrode 100 may comprise acopper layer having a thickness of ˜0.0028″, a polyimide film layerhaving a thickness of ˜0.003″, and an adhesive layer having a thicknessof ˜0.001″ for a total thickness of ˜0.0068″. It will be appreciatedthat the thicknesses of the individual layers ad the total thickness mayvary based on the particular implementation details.

II. Flexible Circuit Electrode Including Dielectric and/or Nonstickand/or Annular Elements Flexible Circuit Electrode IncludingElectrically Conductive and Insulative Elements

FIGS. 10-17 illustrate a flexible circuit electrode 200 comprising atleast one electrically conductive element 204 and at least oneelectrically insulative element 206, according to one aspect of thepresent disclosure. The at least one electrically insulative element 206may be configured to establish a desired gap between electrodes inbipolar electrosurgical instruments, to prevent the electrodes fromshorting, to prevent tissue from sticking to the element, and/or toassist tissue grasping.

FIG. 10 is a perspective view of the electrically conductive side of aflexible circuit electrode 200 comprising at least one electricallyconductive element 204 and at least one electrically insulative element206, according to one aspect of the present disclosure. In one aspect, aplurality of electrically insulative elements 206 may be disposed on theelectrically conductive element 204. In one aspect, each of theelectrically insulative elements 206 comprises an annular wall 216formed on the tissue contacting surface of the electrically conductiveelement 204 and defines a cavity 218 within the annular wall 216. FIG.11 is a perspective view of the flexible circuit electrode 200 shown inFIG. 10 showing the electrically insulative element 210 side of theflexible circuit electrode 200, according to one aspect of the presentdisclosure. In one aspect, the annular wall 216 and cavity 218 geometryof the electrically insulative elements 206 provide nonstick propertiesto prevent or minimize tissue sticking to thereto.

FIG. 12 is a plan view of the electrically conductive element 204 sideof the flexible circuit electrode 200 shown in FIG. 10, according to oneaspect of the present disclosure. FIG. 13 is a plan view of theelectrically insulative element 210 side of the flexible circuitelectrode 200 shown in FIG. 10, according to one aspect of the presentdisclosure.

FIG. 14 is a side elevation view of the flexible circuit electrode 200shown in FIG. 10, according to one aspect of the present disclosure.FIG. 15 is an elevation view of the flexible circuit electrode 200 shownin FIG. 10 taken from a distal end 212, according to one aspect of thepresent disclosure. FIG. 16 is an elevation view of the flexible circuitelectrode 200 shown in FIG. 10 taken from a proximal end 214, accordingto one aspect of the present disclosure. FIG. 17 is a detail view of theflexible circuit electrode 200 shown in FIG. 10, according to one aspectof the present disclosure.

With reference now to FIGS. 10-17, the electrode 200 can be attachedeither to the upper jaw member, the lower jaw member, or both, of aclamp jaw assembly of the electrosurgical instrument. The electrode 200comprises a lead 202 for connecting the electrode 200 to an energysource, such, for example, a radio frequency (RF) generator that outputsenough power to seal tissue. The short lead 202 enables the electrode200 to be connected to the energy source near the distal end of the endeffector. A longer lead may be provided where it is desirable to connectthe electrode 200 to an energy source at the handle portion of theelectrosurgical device.

In one aspect, an electrically insulative layer 205 may be provided onthe at least one electrically conductive element 204 to preventelectrically shorting the jaw member electrodes when they are in aclosed configuration. In another aspect, the electrically insulativelayer 205 defines at least one electrically insulative element 206 toestablish a predetermined gap between the jaw electrodes of a bipolarelectrosurgical instrument. In yet another aspect, the electricallyinsulative layer 205 may be configured as an electrically insulativecover that further defines the electrically conductive element 204 andcan act as a spacer. The electrically insulative element 206 may bedefined by the electrically insulative layer 205 and can be configuredas an electrically insulative barrier between the jaw electrodes,provide a predetermined gap between the jaw electrodes, and/or assisttissue grasping between the jaw electrodes. In one aspect, theelectrically insulative elements 206 may comprise a nonstick coating ormay be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 206 may be formed of a dielectric material.

In one aspect, the electrically insulative layer 205 may be formed bybonding a dielectric cover film on the electrically conductive element204. In one aspect, the electrically insulative elements 206 may beformed by etching the dielectric cover film bonded to the tissuecontacting surface of the electrically conductive element 204. In oneaspect, at least one of the electrically insulative elements 206 may beconfigured as a spacer to provide a predetermined gap between upper andlower electrodes.

The electrically conductive element 204 comprises electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. In one aspect, theelectrically insulative layer 205 further defines the at least oneelectrically conductive element 204. One or more than one of theelectrically conductive elements 204 may be configured and arranged todefine a conductive electrode.

The flexible circuit electrode 200 defines a knife slot 208 that extendsalong a length of the flexible circuit electrode 200. The knife portionof the electrosurgical instrument 2 (FIG. 1A) is slidably movable withinthe knife slot 208 to cut the tissue after it has been sealed usingelectrosurgical energy. Although generally speaking the knife slot 208is located along the lateral center of the flexible circuit electrode200, this is not necessarily always the case. Thus, in other aspects,the knife slot 208 may be offset from the center to either side of theflexible circuit electrode 200.

The electrically insulative element 210 of the flexible circuitelectrode 200 is formed of electrically insulative material such as apolymer and more specifically can be an electrically insulative material(e.g., polyimide, polyester, fluorocarbon, or any polymeric material, orany combinations thereof). The electrically insulative element 210 isgenerally attached to the tissue contacting side of the upper or lowerjaw members of the clamp jaw assembly.

In one aspect, the electrically insulative elements 206 may comprise anonstick coating or may be formed of a nonstick material such as TEFLON.Any nonstick material or nonstick surface finish may be suitable toprevent tissue from sticking to the electrically conductive element 204of the flexible circuit electrode 200. As illustrated most clearly inFIG. 17, dielectric nonstick annular elements 206 may be configured todefine a ring like or donut like structure. Such a structure, however,should not be construed as limiting the dielectric nonstick annularelements 206 to the disclosed form.

III. Segmented Offset Flexible Circuit Electrode End Effector IncludingIndependently Energizable Flexible Circuit Electrodes Configured toProvide Offset Current Paths

FIG. 18 illustrates an end effector 300 comprising four flexible circuitelectrodes 302 a, 302 b, 304 a, 304 b that can be independentlyenergized and configured to provide an offset current path 314, 316according to one aspect of the present disclosure. The end effector 300comprises a clamp jaw assembly comprising an upper jaw 310 a and a lowerjaw 310 b. The lower jaw 310 b is fixed and the upper jaw 310 a ispivotally movable relative to the lower jaw 310 b from an open positionto a closed position and vice versa. In other aspects, the upper jaw maybe fixed and the lower jaw may be movable. In other aspects, both theupper and lower jaws may be movable.

Two of the flexible circuit electrodes 302 a, 304 a are attached to theupper jaw 310 a and the other two flexible circuit electrodes 302 b, 304b are attached to the lower jaw 310 b. A first gap 312 a is providedbetween the two upper jaw 310 a electrodes 302 a, 304 a to electricallyisolate them and provide two independent sections. Likewise, a secondgap 312 b is provided between the two lower jaw 310 b electrodes 302 b,304 b to electrically isolate them and provide two more independentsections. The four electrodes 302 a, 302 b, 304 a, 304 b can beindependently energized to create a first independent offset currentpath 314 between the upper jaw 310 a electrode 304 a and the lower jaw310 b electrode 302 b. A second offset current path 316 is createdbetween the upper jaw 310 a electrode 302 a and the lower jaw 310 belectrode 304 b. Other current paths can be created by independentlyenergizing and grounding the four electrodes 302 a, 302 b, 304 a, 304 b.

The lower jaw 310 b electrodes 302 b, 304 b include an electricallyinsulative layer 305 that defines at least one electrically insulativeelement 306 (e.g., insulative elements to establish desired gaps betweenelectrodes in bipolar electrosurgical instruments, assist tissuegripping, and electrically isolate the electrodes). In one aspect,multiple electrically insulative elements 306 may be defined by theelectrically insulative layer 305 on the lower jaw 310 b electrodes 302b, 304 b may be configured as elements as discussed previously herein,which in one aspect may define an annular configuration. The tissuecontacts the electrodes 302 b, 304 b in between the electricallyinsulative elements 306. Knife slots 308 a is defined in the upper jaw310 a and electrode 304 a and another knife slot 308 b is defined in thelower jaw 310 b and electrode 304 b.

It will be appreciated that is some aspects, only the upper jawelectrodes can be isolated or the lower jaw electrodes can be isolated.Still in other aspects, the end effector 300 may be fitted with theelectrode 100 shown in FIGS. 5-9 or the electrode 200 shown in FIGS.10-17, in which case neither the upper nor the lower jaw electrodesinclude an isolation gap.

In one aspect, an electrically insulative layer 305 may be provided onat least one of the electrodes 302 a, 302 b, 304 a, 304 b to preventelectrically shorting the jaw member electrodes 302 a, 302 b, 304 a, 304b when they are in a closed configuration. In another aspect, theelectrically insulative layer 305 defines at least one electricallyinsulative element 306 to establish a predetermined gap between the jawelectrodes 302 a, 302 b, 304 a, 304 b of the bipolar electrosurgicalinstrument. In yet another aspect, the electrically insulative layer 305may be configured as an electrically insulative cover that furtherdefines the electrodes 302 a, 302 b, 304 a, 304 b and can act as aspacer. The electrically insulative element 306 may be defined by theelectrically insulative layer 305 and can be configured as anelectrically insulative barrier between the jaw electrodes, provide apredetermined gap between the jaw electrodes, and/or assist tissuegrasping between the jaw electrodes. In one aspect, the electricallyinsulative elements 306 may comprise a nonstick coating or may be formedof a nonstick material such as TEFLON to prevent tissue from stickingthereto. In one aspect, the electrically insulative element may beformed of a dielectric material.

In one aspect, the electrically insulative layer 305 may be formed bybonding a dielectric cover film on the electrically conductive elements304 a, 304 b. In one aspect, the electrically insulative elements 306may be formed by etching the dielectric cover film bonded to the tissuecontacting surface of the electrically conductive elements 304 a, 304 b.In one aspect, at least one of the electrically insulative elements 306may be configured as a spacer to provide a predetermined gap betweenupper and lower electrodes.

The electrodes 302 a, 302 b, 304 a, 304 b comprise electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. One or more than one ofthe electrically conductive electrodes 302 a, 302 b, 304 a, 304 b may beconfigured and arranged to define a conductive electrode.

FIG. 19 illustrates the end effector 300 shown in FIG. 18 comprisingfour flexible circuit electrodes 302 a, 302 b, 304 a, 304 b that can beindependently energized and configured to provide a first and seconddirect current path 318, 320, according to one aspect of the presentdisclosure. In the example illustrate din FIG. 19, the electrodes 302 a,302 b, 304 a, 304 b are configured to set up a first direct current path318 between the upper electrode 302 a and the lower electrode 302 b anda second current path 320 between the upper electrode 304 a and thelower electrode 304 b. Knife slots 308 a is defined in the upper jaw 310a and electrode 304 a and another knife slot 308 b is defined in thelower jaw 310 b and electrode 304 b.

With reference now to FIGS. 18 and 19, with the flexible circuittechnology the segmented electrodes 302 a, 302 b, 304 a, 304 b can becost effectively manufactured to provide control over independentsections of the electrodes 302 a, 302 b, 304 a, 304 b. This techniqueprovides offset electrode functionality and tissue impedance sensing persection of the jaw with subsequent tailored control of the power appliedto that section of tissue. The electrodes 302 a, 302 b, 304 a, 304 b canbe cost effectively manufactured and provide multiple isolated zonesindependently controlled.

FIGS. 20-26 illustrate a segmented offset flexible circuit electrode400, according to one aspect of the present disclosure. The segmentedoffset flexible circuit electrode 400 is configured to be attached tothe end effector 300 shown in FIGS. 18 and 19. The electrode 400 can beattached either to the upper jaw member, the lower jaw member, or both,of a clamp jaw assembly of the electrosurgical instrument.

FIG. 20 is a perspective view of the electrically conductive elements404 side of a segmented offset flexible circuit electrode 400 comprisingtwo electrode segments 404 a, 404 b of the electrically conductiveelement 404, according to one aspect of the present disclosure. The twoelectrode segments 404 a, 404 b are electrically isolated from eachother. FIG. 21 is a perspective view of the electrically insulativeelement 410 side of the segmented offset flexible circuit electrode 400shown in FIG. 20, according to one aspect of the present disclosure.

FIG. 22 is a plan view of the electrically conductive element 404 sideof the segmented offset flexible circuit electrode 400 shown in FIG. 20,according to one aspect of the present disclosure. FIG. 23 illustrates aplan view of the electrically insulative element 410 side of thesegmented offset flexible circuit electrode 400 shown in FIG. 20,according to one aspect of the present disclosure.

FIG. 24 is a side elevation view of the segmented offset flexiblecircuit electrode 400 shown in FIG. 20, according to one aspect of thepresent disclosure. FIG. 25 is an elevation view of the segmented offsetflexible circuit electrode 400 shown in FIG. 20 taken from a distal end412, according to one aspect of the present disclosure. FIG. 26 is anelevation view of the segmented offset flexible circuit electrode 400shown in FIG. 20 taken from a proximal end 414, according to one aspectof the present disclosure.

With reference now to FIGS. 20-26, the segmented offset flexible circuitelectrode 400 comprises a lead 402 for connecting the flexible circuitelectrode 400 to an energy source, such, for example, a radio frequency(RF) generator that outputs enough power to seal tissue. The short lead402 enables the electrode 400 to be connected to the energy source nearthe distal end of the end effector. A longer lead may be provided whereit is desirable to connect the electrode 400 to an energy source at thehandle portion of the electrosurgical device.

The electrode 400 can be attached either to the upper jaw member, thelower jaw member, or both, of a clamp jaw assembly of theelectrosurgical instrument, as shown in FIGS. 18 and 19, for example.The electrically conductive element 404 comprises two segments 404 a,404 b. A gap 416 is provided between the segments 404 a, 404 belectrically isolated them from each other. The electrode 400 furthercomprises a knife slot 408. The knife portion of the electrosurgicalinstrument 2 (FIG. 1A) is slidably movable within the knife slot 408 tocut the tissue after it has been sealed using electrosurgical energy.

In one aspect, an electrically insulative layer 405 may be provided onthe at least one electrically conductive elements 404 a, 404 b toprevent electrically shorting the jaw member electrodes when they are ina closed configuration. In another aspect, the electrically insulativelayer 405 defines at least one electrically insulative element 406 toestablish a predetermined gap between the jaw electrodes of a bipolarelectrosurgical instrument. In yet another aspect, the electricallyinsulative layer 405 may be configured as an electrically insulativecover that further defines the electrically conductive elements 404 a,404 b and can act as a spacer. The electrically insulative element 406may be defined by the electrically insulative layer 405 and can beconfigured as an electrically insulative barrier between the jawelectrodes, provide a predetermined gap between the jaw electrodes,and/or assist tissue grasping between the jaw electrodes. In one aspect,the electrically insulative elements 406 may comprise a nonstick coatingor may be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 406 may be formed of a dielectric material.

In one aspect, the electrically insulative layer 405 may be formed bybonding a dielectric cover film on the electrically conductive element404. In one aspect, the electrically insulative elements 406 may beformed by etching the dielectric cover film bonded to the electricallyconductive element 404. In one aspect, at least one of the electricallyinsulative elements 406 is configured as a spacer to provide apredetermined gap between upper and lower electrodes.

The electrically conductive elements 404 a, 404 b comprise electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. One or more than one ofthe electrically conductive elements 404 may be configured and arrangedto define a conductive electrode.

The flexible circuit electrode 400 defines a knife slot 408 that extendsalong a length of the electrode 400. Although generally speaking theknife slot 408 is laterally centered, this is not necessarily always thecase, and in other aspects, the knife slot 408 may be laterally offsetfrom center.

The electrically insulative element 410 of the flexible circuitelectrode 400 is formed of electrically insulative material such as apolymer and more specifically can be an electrically insulative material(e.g., polyimide, polyester, fluorocarbon, or any polymeric material, orany combinations thereof). The electrically insulative element 410 isgenerally attached to the tissue contacting side of the upper or lowerjaw members of the clamp jaw assembly.

IV. Flexible Circuit Electrode Including Electrically InsulativeElements A. Flexible Circuit Electrode Including Electrically InsulativeElements

FIGS. 27-33 illustrate a flexible circuit electrode 500 comprisingelectrically insulative elements 506 (e.g., insulative elements toestablish desired gaps between electrodes in bipolar electrosurgicalinstruments), according to one aspect of the present disclosure.

FIG. 27 is a perspective view of a flexible circuit electrode 500comprising an array of electrically insulative elements 506 showing theelectrically conductive element 504 side, according to one aspect of thepresent disclosure. FIG. 28 is a perspective view of the electricallyinsulative element 510 side of the flexible circuit electrode 500 shownin FIG. 27, according to one aspect of the present disclosure.

FIG. 29 is a plan view of the electrically conductive element 504 sideof the flexible circuit electrode 500 shown in FIG. 27, according to oneaspect of the present disclosure. FIG. 30 is a plan view of theelectrically insulative element 510 side of the flexible circuitelectrode 500 shown in FIG. 27, according to one aspect of the presentdisclosure.

FIG. 31 is a side elevation view of the flexible circuit electrode 500shown in FIG. 27, according to one aspect of the present disclosure.FIG. 32 is an elevation view of the flexible circuit electrode 500 shownin FIG. 27 taken from a distal end 512, according to one aspect of thepresent disclosure. FIG. 33 is an elevation view of the flexible circuitelectrode 500 shown in FIG. 27 taken from a proximal end 514, accordingto one aspect of the present disclosure.

With reference now to FIGS. 27-33, the electrode 500 can be attachedeither to the upper jaw member, the lower jaw member, or both, of aclamp jaw assembly of the electrosurgical instrument.

The electrode 500 comprises a lead 502 for connecting the electrode 500to an energy source, such, for example, a radio frequency (RF) generatorthat outputs enough power to seal tissue. The short lead 502 enables theelectrode 500 to be connected to the energy source near the distal endof the end effector. A longer lead may be provided where it is desirableto connect the electrode 500 to an energy source at the handle portionof the electrosurgical device.

In one aspect, an electrically insulative layer 505 may be provided onthe at least one electrically conductive element 504 to preventelectrically shorting the jaw member electrodes when they are in aclosed configuration. In another aspect, the electrically insulativelayer 505 defines at least one electrically insulative element 506 toestablish a predetermined gap between the jaw electrodes of a bipolarelectrosurgical instrument. In yet another aspect, the electricallyinsulative layer 505 may be configured as an electrically insulativecover that further defines the electrically conductive element 504 andcan act as a spacer. The electrically insulative element 506 may bedefined by the electrically insulative layer 505 and can be configuredas an electrically insulative barrier between the jaw electrodes,provide a predetermined gap between the jaw electrodes, and/or assisttissue grasping between the jaw electrodes. In one aspect, theelectrically insulative elements 506 may comprise a nonstick coating ormay be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 506 may be formed of a dielectric material.

In one aspect, the electrically insulative layer 505 may be formed bybonding a dielectric cover film on the electrically conductive element504. In one aspect, the electrically insulative elements 506 may beformed by etching the dielectric cover film bonded to the electricallyconductive element 504. In one aspect, at least one of the electricallyinsulative elements 506 may be configured as a spacer to provide apredetermined gap between upper and lower electrodes.

The electrically conductive element 504 comprises electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. One or more than one ofthe electrically conductive elements 504 may be configured and arrangedto define a conductive electrode.

As shown in FIGS. 27 and 31, the array of electrically insulativeelements 506 may be provided on a distal portion of the electrode 500.Nevertheless, the array of electrically insulative elements 506 can beprovided along the full length of the conductive element 504 side of theelectrode 500.

The flexible circuit electrode 500 defines a knife slot 508 that extendsalong a length of the flexible circuit electrode 500. Although generallyspeaking the knife slot 508 is located along the lateral center of theflexible circuit electrode 500, this is not necessarily always the case.Thus, in other aspects, the knife slot 508 may be offset from the centerto either side of the flexible circuit electrode 500. The knife portionof the electrosurgical instrument 2 (FIG. 1A) is slidably movable withinthe knife slot 508 to cut the tissue after it has been sealed usingelectrosurgical energy.

The electrically insulative element 510 of the flexible circuitelectrode 500 is formed of electrically insulative material such as apolymer and more specifically can be an electrically insulative material(e.g., polyimide, polyester, fluorocarbon, or any polymeric material, orany combinations thereof). The electrically insulative element 510 isgenerally attached to the tissue contacting side of the upper or lowerjaw members of the clamp jaw assembly.

B. Integrated Flexible Circuit Electrode Including ElectricallyInsulative Elements

FIGS. 34-35 illustrate an integrated flexible circuit electrode 600comprising electrically insulative elements 606 (e.g., insulativeelements to establish desired gaps between electrodes in bipolarelectrosurgical instruments), according to one aspect of the presentdisclosure.

FIG. 34 is a perspective view of an integrated flexible circuitelectrode 600 comprising electrically insulative elements 606 showingthe electrically conductive element 604 side of the integrated flexiblecircuit electrode 600, according to one aspect of the presentdisclosure. FIG. 35 is a section view of the integrated flexible circuitelectrode 600 shown in FIG. 34 taken through one of the electricallyinsulative elements 606, according to one aspect of the presentdisclosure.

With reference now to FIGS. 34-35, the electrode 600 can be attachedeither to the upper jaw member, the lower jaw member, or both, of aclamp jaw assembly of the electrosurgical instrument. Attachmentfeatures 616 are provided on the electrode 600 to attach the electrodeto the jaws of the end effector.

The electrode 600 comprises a lead 602 for connecting the electrode 600to an energy source, such, for example, a radio frequency (RF) generatorthat outputs enough power to seal tissue. The short lead 602 enables theelectrode 600 to be connected to the energy source near the distal endof the end effector. A longer lead may be provided where it is desirableto connect the electrode 600 to an energy source at the handle portionof the electrosurgical device.

The electrode 600 also comprises an electrically conductive element 604and a knife slot 608. The electrically conductive element 604 of theflexible circuit electrode 600 also includes one or more electricallyinsulative elements 606 formed thereon to prevent the electricallyconductive element 604 from electrically shorting when the jaw membersare in a closed configuration and to prevent tissue from sticking to theelectrically conductive element 604. The tissue contacts theelectrically conductive element 604 in between the electricallyinsulative elements 606.

In one aspect, an electrically insulative layer 605 may be provided onthe at least one electrically conductive element 604 to preventelectrically shorting the jaw member electrodes when they are in aclosed configuration. In another aspect, the electrically insulativelayer 605 defines at least one electrically insulative element 606 toestablish a predetermined gap between the jaw electrodes of a bipolarelectrosurgical instrument. In yet another aspect, the electricallyinsulative layer 605 may be configured as an electrically insulativecover that further defines the electrically conductive element 604 andcan act as a spacer. The electrically insulative element 606 may bedefined by the electrically insulative layer 605 and can be configuredas an electrically insulative barrier between the jaw electrodes,provide a predetermined gap between the jaw electrodes, and/or assisttissue grasping between the jaw electrodes. In one aspect, theelectrically insulative elements 606 may comprise a nonstick coating ormay be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 606 may be formed of a dielectric material.

In one aspect, the electrically insulative layer 605 may be formed bybonding a dielectric cover film on the electrically conductive element604. In one aspect, the electrically insulative elements 606 may beformed by etching the dielectric cover film bonded to the electricallyconductive element 604. In one aspect, at least one of the electricallyinsulative elements 606 may be configured as a spacer to provide apredetermined gap between upper and lower electrodes.

The electrically conductive element 604 comprises electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. One or more than one ofthe electrically conductive elements 604 may be configured and arrangedto define a conductive electrode.

The electrically insulative element 610 of the flexible circuitelectrode 600 is formed of electrically insulative material such as apolymer and more specifically can be an electrically insulative material(e.g., polyimide, polyester, fluorocarbon, or any polymeric material, orany combinations thereof). The electrically insulative element 610 isgenerally attached to the tissue contacting side of the upper or lowerjaw members of the clamp jaw assembly.

The knife portion of the electrosurgical instrument 2 (FIG. 1A) isslidably movable within the knife slot 608 to cut the tissue after ithas been sealed using electrosurgical energy. The knife slot 608 extendsalong a length of the flexible circuit electrode 600. Although generallyspeaking the knife slot 608 is located along the lateral center of theflexible circuit electrode 600, this is not necessarily always the case.Thus, in other aspects, the knife slot 608 may be offset from the centerto either side of the flexible circuit electrode 600.

Still with reference to FIGS. 35-36, utilizing flex circuit technologyprovides a means to manufacture the low cost electrode 600 assembly withcontrol over the geometry of the elements 606. Tissue sticking may be afunction of the surface area of the electrode 600. This manufacturingmethod provides a high degree of control over this variable. Thus, thelow cost RF electrode 600 provides superior sealing with potentiallyless sticking.

The examples described in connection with FIGS. 36-40 illustrate variousgeometric patterns or configurations of electrically insulative elementsto insulate the upper and lower jaw from shorting, provide apredetermined gap between the upper and lower jaw, and/or assist tissuegripping. Please not that the upper and lower jaws could both containthese patterns such that they offset from one another.

FIG. 36 is a schematic diagram of an end effector 720 comprising anupper jaw 720 a and a lower jaw 720 b and flexible circuit electrodes700 a, 700 b attached to the corresponding upper and lower jaws 720 a,720 b where the flexible circuit electrodes 700 a, 700 b compriseelectrically insulative elements 706 a, 706 b (e.g., insulative elementsto establish desired gaps between electrodes in bipolar electrosurgicalinstruments), according to one aspect of the present disclosure. FIG. 37is a plan view of the flexible circuit electrode 700 a, 700 b comprisinga macro pattern of electrically insulative elements 706 a, 706 b showingthe tissue contacting surface thereof, according to one aspect of thepresent disclosure. FIG. 38 is a detail view of the flexible circuitelectrode 700 a, 700 b shown in FIG. 37, according to one aspect of thepresent disclosure.

With reference to FIGS. 36-38, the end effector 720 comprises flexiblecircuit electrodes 700 a, 700 b on the upper and lower jaws 720 a, 720b. The flexible circuit electrodes 700 a, 700 b each comprises anelectrically conductive element 704 a, 704 b and a macro pattern ofelectrically insulative elements 706 a, 706 b formed on a surface of theAs shown in FIG. 37, one or both of the electrically conductive elements704 a, 704 b. The tissue contacts the conductive elements 704 a, 704 bbetween the electrically insulative elements 706 a, 706 b. As shownparticularly in FIG. 38, electrically insulative elements 710 a, 710 bare attached or bonded to the conductive elements 704 a, 704 b on theside that is opposite side of the tissue contacting side.

In one aspect, electrically insulative layers 705 a, 705 b may beprovided on the least one electrically conductive elements 704 a, 704 bto prevent electrically shorting the jaw member electrodes when they arein a closed configuration. In another aspect, the electricallyinsulative layers 705 a, 705 b defines electrically insulative elements706 a, 706 b to establish a predetermined gap between the jaws 720 a,720 b of a bipolar electrosurgical instrument. In yet another aspect,the electrically insulative layers 705 a, 705 b may be configured as anelectrically insulative cover that further defines the electricallyconductive elements 704 a, 704 b and can act as a spacer. Theelectrically insulative elements 706 a, 706 b may be defined by thecorresponding electrically insulative layers 705 a, 705 b and can beconfigured as an electrically insulative barrier between the jawelectrodes, provide a predetermined gap between the jaw electrodes,and/or assist tissue grasping between the jaw electrodes. In one aspect,the electrically insulative elements 706 a, 706 b may comprise anonstick coating or may be formed of a nonstick material such as TEFLONto prevent tissue from sticking thereto. In one aspect, the electricallyinsulative elements 706 a, 706 b may be formed of a dielectric material.

In one aspect, the electrically insulative layers 705 a, 705 b may beformed by bonding dielectric cover films on the electrically conductiveelements 704 a, 704 b. In one aspect, the electrically insulativeelements 706 a, 706 b may be formed by etching the dielectric coverfilms bonded to the electrically conductive elements 704 a, 704 b. Inone aspect, at least one of the electrically conductive elements 704 a,704 b may be configured as a spacer to provide a predetermined gapbetween upper and lower electrodes.

The electrically conductive elements 704 a, 704 b comprise electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. One or more than one ofthe electrically conductive elements 704 a, 704 b may be configured andarranged to define a conductive electrode.

FIG. 39 illustrates a flexible circuit electrode 800 comprising apattern of electrically insulative elements 806 (e.g., insulativeelements to establish desired gaps between electrodes in bipolarelectrosurgical instruments), according to one aspect of the presentdisclosure. FIG. 40 is a detail view of the flexible circuit electrode800 shown in FIG. 39, according to one aspect of the present disclosure.

With reference now to FIGS. 39 and 40, the flexible electrode 800comprises a pattern of electrically insulative elements 806 formed on atleast one electrically conductive element 804. The pattern ofelectrically insulative elements 806 can be uniform or substantiallyevenly distributed across the flexible circuit electrode 800 andcomprises ten or more electrically insulative elements 806, for example.An electrically insulative element 810 is attached or bonded to theelectrically conductive element 810 on the side that is opposite to thetissue contacting side. As shown particularly in FIG. 40, theelectrically insulative elements 806 have a cylindrical lower portionand a dome-like upper portion with a flat section thereon. Theelectrically insulative elements 806 have a diameter ranging from˜0.001″ to ˜0.002″ and a height ranging from ˜0.002″ to ˜0.0025″, forexample.

In one aspect, an electrically insulative layer 805 may be provided onthe at least one electrically conductive element 804 to preventelectrically shorting the jaw member electrodes when they are in aclosed configuration. In another aspect, the electrically insulativelayer 805 defines at least one electrically insulative element 806 toestablish a predetermined gap between the jaw electrodes of a bipolarelectrosurgical instrument. In yet another aspect, the electricallyinsulative layer 805 may be configured as an electrically insulativecover that further defines the electrically conductive element 804 andcan act as a spacer. The electrically insulative element 806 may bedefined by the electrically insulative layer 805 and can be configuredas an electrically insulative barrier between the jaw electrodes,provide a predetermined gap between the jaw electrodes, and/or assisttissue grasping between the jaw electrodes. In one aspect, theelectrically insulative elements 806 may comprise a nonstick coating ormay be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 806 may be formed of a dielectric material.

In one aspect, the electrically insulative layer 805 may be formed bybonding a dielectric cover film on the electrically conductive element804. In one aspect, the electrically insulative elements 806 may beformed by etching the dielectric cover film bonded to the electricallyconductive element 804. In one aspect, at least one of the electricallyinsulative elements 806 may be configured as a spacer to provide apredetermined gap between upper and lower electrodes.

The electrically conductive element 804 comprises electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. One or more than one ofthe electrically conductive elements 804 may be configured and arrangedto define a conductive electrode.

V. Flexible Circuit Electrode Including Thermal Isolation and DistalElectrode Element A. End Effector Including Thermally Isolated FlexibleCircuit Electrodes and Distal Electrode Element

FIG. 41 illustrates an end effector 930 comprising an upper jaw 920 aand a lower jaw 920 b and flexible circuit electrodes 900 a, 900 battached to the corresponding upper and lower jaws 920 a, 920 b, andwhere the flexible circuit electrode 900 b attached to the lower jaw 920b comprises a thermal isolation and a distal electrode element 922 orelement having a tongue configuration, according to one aspect of thepresent disclosure. The upper and lower electrode 900 a, 900 b comprisesa knife slot 908 a, 908 b. The lower jaw 920 b electrode 900 b comprisesa plurality of electrically insulative elements 906 (e.g., insulativeelements to establish desired gaps between electrodes in bipolarelectrosurgical instruments). Each of upper and lower jaw 920 a, 920 belectrodes 900 a, 900 b comprises a lead 902 a, 902 b to connect theelectrodes 900 a, 900 b to an RF energy source.

During use of RF electrosurgical instruments, the thermal mass of thejaws can cause thermal imbalances of the heat flow from and into thetissue. Employing flexible circuit technology, the flexible circuitelectrode 900 a, 900 b can be applied to both the upper and lower jaws920 a, 920 b to thermally isolate the jaws 920 a, 920 b from theelectrically conductive elements 904 a, 904 b, which define theelectrode tissue sealing surfaces, thus ensuring that more heat isapplied to the tissue and not lost through thermal conductivity in thejaws 920 a, 920 b. Examples of potential material for the electrodes 900a, 900 b include Pyralux LF9250 and Pyralux LF9230 both sold by DuPont.

In one aspect, an electrically insulative layer 905 may be provided onthe at least one electrically conductive element 904 b to preventelectrically shorting the electrically conductive element 904 a, 904 bof the jaw member electrodes when they are in a closed configuration. Inanother aspect, the electrically insulative layer 905 defines at leastone electrically insulative element 906 to establish a predetermined gapbetween the jaw electrodes of a bipolar electrosurgical instrument. Inyet another aspect, the electrically insulative layer 905 may beconfigured as an electrically insulative cover that further defines theelectrically conductive element 904 a, 904 b and can act as a spacer.The electrically insulative element 906 may be defined by theelectrically insulative layer 905 and can be configured as anelectrically insulative barrier between the jaw electrodes, provide apredetermined gap between the jaw electrodes, and/or assist tissuegrasping between the jaw electrodes. In one aspect, the electricallyinsulative element 906 may comprise a nonstick coating or may be formedof a nonstick material such as TEFLON to prevent tissue from stickingthereto.

The electrically conductive elements 904 a, 904 b each compriseselectrically conductive material such as copper, gold plated copper,silver, platinum, stainless steel, aluminum, or any suitableelectrically conductive biocompatible material, for example. One or morethan one of the electrically conductive elements 904 a, 904 b may beconfigured and arranged to define a conductive electrode.

FIGS. 42-48 illustrate a flexible circuit electrode 900 b comprising adistal electrode element 922 and electrically insulative elements 906,according to one aspect of the present disclosure. FIG. 42 is aperspective view of a flexible circuit electrode 900 b comprising adistal electrode element 922 and electrically insulative elements 906showing the electrically conductive element 904 b that defines theelectrode tissue sealing surface, according to one aspect of the presentdisclosure. FIG. 43 is a perspective view of the electrically insulativeelement 906 of the flexible circuit electrode 900 b shown in FIG. 42,according to one aspect of the present disclosure.

FIG. 44 is a plan view of the electrically conductive element 904 b sideof the flexible circuit electrode 900 b shown in FIG. 42, according toone aspect of the present disclosure. FIG. 45 is a plan view of theelectrically insulative element 910 b of the flexible circuit electrode900 b shown in FIG. 42, according to one aspect of the presentdisclosure.

FIG. 46 is a side elevation view of the flexible circuit electrode 900 bshown in FIG. 42, according to one aspect of the present disclosure.FIG. 47 is an elevation view of the flexible circuit electrode 900 bshown in FIG. 42 taken from a distal end 912, according to one aspect ofthe present disclosure. FIG. 48 is an elevation view of the flexiblecircuit electrode 900 b shown in FIG. 42 taken from a proximal end 914,according to one aspect of the present disclosure.

With reference now to FIGS. 42-48, the flexible circuit electrode 900 bcomprises a lead 902 b for connecting the electrode 900 b to an energysource, such, for example, a radio frequency (RF) generator that outputsenough power to seal tissue. The short lead 902 b enables the electrode900 b to be connected to the energy source near the distal end of theend effector. A longer lead may be provided where it is desirable toconnect the electrode 900 b to an energy source at the handle portion ofthe electrosurgical device.

The electrode 900 b can be attached either to the upper jaw member, thelower jaw member, or both, of a clamp jaw assembly of theelectrosurgical instrument, as shown in FIG. 41, for example. In oneaspect, an electrically insulative layer 905 may be provided on the atleast one electrically conductive element 904 to prevent electricallyshorting the jaw member electrodes when they are in a closedconfiguration. In another aspect, the electrically insulative layer 905defines at least one electrically insulative element 906 to establish apredetermined gap between the jaw electrodes of a bipolarelectrosurgical instrument. In yet another aspect, the electricallyinsulative layer 905 may be configured as an electrically insulativecover that further defines the electrically conductive element 904 b andcan act as a spacer. The electrically insulative element 906 may bedefined by the electrically insulative layer 905 and can be configuredas an electrically insulative barrier between the jaw electrodes,provide a predetermined gap between the jaw electrodes, and/or assisttissue grasping between the jaw electrodes. In one aspect, theelectrically insulative element 906 may comprise a nonstick coating ormay be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 906 may be formed of a dielectric material.

In one aspect, the electrically insulative layer 905 may be formed bybonding a dielectric cover film on the electrically conductive element904 b. In one aspect, the electrically insulative elements 906 may beformed by etching the dielectric cover film bonded to the electricallyconductive element 904 b. In one aspect, at least one of theelectrically insulative elements 906 may be configured as a spacer toprovide a predetermined gap between upper and lower electrodes.

The electrically conductive element 904 b comprises the non-isolateddistal electrode element 922. The electrically conductive element 904 bcomprises electrically conductive material such as copper, gold platedcopper, silver, platinum, stainless steel, aluminum, or any suitableelectrically conductive biocompatible material, for example. One or morethan one of the electrically conductive elements 904 a, 904 b may beconfigured and arranged to define a conductive electrode.

The flexible circuit electrode 900 b further comprises a knife slot 908b. The knife portion of the electrosurgical instrument 2 (FIG. 1A) isslidably movable within the knife slot 908 b to cut the tissue after ithas been sealed using electrosurgical energy. The flexible circuitelectrode 900 b defines the knife slot 908 b and extends along a lengthof the electrode 900 b. Although generally speaking the knife slot 908 bis laterally centered, this is not necessarily always the case, and inother aspects, the knife slot 908 b may be laterally offset from center.

The electrically insulative element 910 b of the flexible circuitelectrode 900 b is formed of electrically insulative material such as apolymer and more specifically can be an electrically insulative material(e.g., polyimide, polyester, fluorocarbon, or any polymeric material, orany combinations thereof). The electrically insulative element 910 b isgenerally attached to the tissue contacting side of the upper or lowerjaw members of the clamp jaw assembly.

B. End Effector Including a Flexible Circuit Electrode IncludingNon-Isolated Distal Electrode Element and Electrically InsulativeElements

FIGS. 49-51 illustrate detail views of a lower jaw portion 920 b of theend effector 930 (FIG. 41) comprising a flexible circuit electrode 904 bcomprising a non-isolated distal electrode element 922 and electricallyinsulative elements 906, according to one aspect of the presentdisclosure.

FIG. 49 is a perspective view of a flexible circuit electrode 904 bcomprising a non-isolated distal electrode element 922, electricallyinsulative elements 906, and a knife slot 908 b according to one aspectof the present disclosure. FIG. 50 is a perspective view of the lowerjaw 920 b, according to one aspect of the present disclosure. FIG. 51 isan elevation view of the lower jaw 920 b of the end effector 930 shownin FIG. 49 taken from a distal end, according to one aspect of thepresent disclosure. The distal end of the lower jaw 920 b comprisesprojections 924 a, 924 b on either side of the non-isolated distalelectrode element 922. As previously described, in one aspect, anelectrically insulative layer 905 may be provided on the at least oneelectrically conductive element 904 b to prevent electrically shortingthe electrically conductive element 904 a, 904 b of the jaw memberelectrodes when they are in a closed configuration.

FIG. 52 is a perspective view of a lower jaw portion 1020 b of an endeffector comprising an isolated distal electrode element 1022, accordingto one aspect of the present disclosure. A flexible circuit electrodeassembly 1000 comprises a primary electrode 1004 and a second electrodeconfigured as an isolated distal electrode element 1022 at the distalend of the flexible circuit electrode assembly 1000. The distalelectrode element 1022 is electrically and thermally isolated from theprimary electrode 1004, which is employed as the main tissue sealingsurface. An adhesive layer 1010 is provided between the primaryelectrode 1004 and the lower jaw member 1020 b. The electricallyinsulative elements 1006 also are disposed on the tissue contactingsurface of the flexible circuit electrode assembly 1000. Theelectrically insulative elements 1006 are sized and configured toprevent electrical shorting of the upper electrode with the primaryelectrode 1004 and to set a predetermined gap between the upper andlower jaw members 1020 b (only the lower jaw member 1020 b is shown forclarity of disclosure). A gap 1024 is provided between the distalelectrode element 1022 and the primary electrode 1004 to thermally andelectrically the distal electrode element 1022 and the primary electrode1004. The distal end of the lower jaw 1020 b comprises projections 1026a, 1026 b on either side of the isolated distal electrode element 1022.

In one aspect, an electrically insulative layer 1005 may be provided onthe at least one electrically conductive element 1004 to preventelectrically shorting the electrically conductive elements of the jawmember electrodes when they are in a closed configuration. In anotheraspect, the electrically insulative layer 1005 defines at least oneelectrically insulative element 1006 to establish a predetermined gapbetween the jaw electrodes of a bipolar electrosurgical instrument. Inyet another aspect, the electrically insulative layer 1005 may beconfigured as an electrically insulative cover that further defines theelectrically conductive element 1004 and can act as a spacer. Theelectrically insulative element 1006 may be defined by the electricallyinsulative layer 1005 and can be configured as an electricallyinsulative barrier between the jaw electrodes, provide a predeterminedgap between the jaw electrodes, and/or assist tissue grasping betweenthe jaw electrodes. In one aspect, the electrically insulative elements1006 may comprise a nonstick coating or may be formed of a nonstickmaterial such as TEFLON to prevent tissue from sticking thereto. In oneaspect, the electrically insulative elements 1006 may be formed of adielectric material.

In one aspect, the electrically insulative layer 1005 may be formed bybonding a dielectric cover film on the electrically conductive element1004. In one aspect, the electrically insulative elements 1006 may beformed by etching the dielectric cover film bonded to the electricallyconductive element 1004. In one aspect, at least one of the electricallyinsulative elements 1006 may be configured as a spacer to provide apredetermined gap between upper and lower electrodes.

The electrically conductive element 1004 each comprises electricallyconductive material such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example. One or more than one ofthe electrically conductive elements 1004 may be configured and arrangedto define a conductive electrode.

VI. Flexible Circuit Electrodes with Flexure Bearing A. Flexible CircuitElectrode Including Upper and Lower Electrodes Coupled by LateralFlexure Bearing

FIGS. 53-59 illustrate a flat flexible circuit electrode 1100 comprisingan upper electrode 1100 a and a lower electrode 1100 b coupled by aflexure bearing 1128, according to one aspect of the present disclosure.The flexure bearing 1128 connects upper and lower flat flexible circuitelectrodes 1104 a, 1104 b that are spaced apart laterally relative tothe flexure bearing 1128.

FIG. 53 is a perspective view of the flat flexible circuit electrode1100 comprising an upper flat flexible circuit electrode 1104 a and alower flat flexible circuit electrode 1104 b showing the electricallyconductive elements 1104 a, 1104 b side, which define the electrodestissue sealing surfaces, according to one aspect of the presentdisclosure. FIG. 54 is a perspective view showing the electricallyinsulative element 1106 a, 1106 b side of the upper and lower flatflexible circuit electrodes 1104 a, 1104 b shown in FIG. 53, accordingto one aspect of the present disclosure.

FIG. 55 is a plan view of the electrically conductive elements 1104 a,1104 b side of the upper and lower flat flexible circuit electrodes 1100a, 1100 b shown in FIG. 53, according to one aspect of the presentdisclosure. FIG. 56 is a plan view of the electrically insulativeelement side 1110 a, 1110 b of the upper and lower flat flexible circuitelectrodes 1100 a, 1100 b shown in FIG. 53, according to one aspect ofthe present disclosure.

FIG. 57 is a side elevation view of the upper and lower flat flexiblecircuit electrodes 1100 a, 1100 b shown in FIG. 53, according to oneaspect of the present disclosure. FIG. 58 is an elevation view of theupper and lower flat flexible circuit electrodes 1100 a, 1100 b shown inFIG. 53 taken from a distal end 1112, according to one aspect of thepresent disclosure. FIG. 59 is an elevation view of the upper and lowerflat flexible circuit electrodes shown in FIG. 53 taken from a proximalend 1114, according to one aspect of the present disclosure.

With reference now to FIGS. 53-59, the flat flexible circuit electrode1100 comprises two separate electrodes, an upper flat flexible electrode1100 a and a lower flat flexible electrode 1100 b that are coupled by aflexure bearing 1128 connecting the two electrodes 1100 a, 1100 b. Inone aspect the flexure bearing 1128 may be a flexure bearing. The flatflexible circuit electrode 1100 comprises a lead 1102 for connecting theupper and lower electrodes 1100 a, 1100 b to an energy source, such, forexample, a radio frequency (RF) generator that outputs enough power toseal tissue. The long lead 1102 enables the upper and lower electrodes1100 a, 1100 b to be connected to the energy source at the handleportion of the electrosurgical device. A shorter longer lead may beprovided where it is desirable to connect the electrodes 1100 a, 1100 bto an energy source near the distal end of the end effector.

The upper electrode 1100 a can be attached to the upper jaw member andthe lower electrode 1100 b can be attached to the lower jaw member of aclamp jaw assembly of the electrosurgical instrument, for example. Theupper electrode 1100 a comprises an electrically conductive element 1104a that includes electrically insulative elements 1106 a (e.g.,insulative rings to establish desired gaps between electrodes in bipolarelectrosurgical instruments) and the lower electrode 1100 b comprises anelectrically conductive element 1104 b that includes electricallyinsulative elements or 1106 b provided thereon. The electricallyinsulative elements 1106 a, 1106 b prevent the electrically conductiveelements 1104 a, 1104 b from electrically shorting when the jaw membersare in a closed configuration. The electrically insulative elements 1106a, 1106 b may be made of a dielectric nonstick material. Theelectrically conductive elements 1104 a, 1104 b comprise electricallyconductive materials such as copper, gold plated copper, silver,platinum, stainless steel, aluminum, or any suitable electricallyconductive biocompatible material, for example.

Each of the upper and lower flat flexible circuit electrodes 1100 a,1100 b further comprise knife slots 1108 a, 1108 b. The knife portion ofthe electrosurgical instrument 2 (FIG. 1A) is slidably movable withinthe knife slots 1108 a, 1108 b to cut the tissue after it has beensealed using electrosurgical energy. The flat flexible circuitelectrodes 1100 a, 1100 b each define a knife slot 1108 a, 1108 b andextends along a length of the electrode 1100. Although generallyspeaking the knife slots 1108 a, 1108 b are laterally centered, this isnot necessarily always the case, and in other aspects, the knife slots1108 a, 1108 b may be laterally offset from center.

The electrically insulative elements 1106 a, 1106 b of the flexiblecircuit electrode 1100 a, 1100 b are formed of electrically insulativematerials such as a polymer and more specifically can be an electricallyinsulative material (e.g., polyimide, polyester, fluorocarbon, or anypolymeric material, or any combinations thereof). The electricallyinsulative elements 1106 a, 1106 b are generally attached to the tissuecontacting side of the upper or lower jaw members of the clamp jawassembly.

In one aspect, electrically insulative layers 1105 a, 1105 b may beprovided on the electrically conductive elements 1104 a, 1104 b toprevent electrically shorting the electrically conductive element 1104a, 1104 b of the jaw member electrodes when they are in a closedconfiguration. In another aspect, the electrically insulative layers1105 a, 1105 b define the electrically insulative elements 1106 a, 1106b to establish a predetermined gap between the jaw electrodes of abipolar electrosurgical instrument. In yet another aspect, theelectrically insulative layers 1105 a, 1105 b may be configured as anelectrically insulative cover that further defines the electricallyconductive elements 1104 a, 1104 b and can act as a spacer. Theelectrically insulative element 906 may be defined by the electricallyinsulative layers 1105 a, 1105 b and can be configured as anelectrically insulative barrier between the jaw electrodes, provide apredetermined gap between the jaw electrodes, and/or assist tissuegrasping between the jaw electrodes. In one aspect, the electricallyinsulative elements 1106 a, 1106 b may comprise a nonstick coating ormay be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 1106 a, 1106 b may be formed of a dielectric material.

In one aspect, the electrically insulative layer 1105 a, 1105 b may beformed by bonding a dielectric cover film on the electrically conductiveelement 1104 a, 1104 b. In one aspect, the electrically insulativeelements 1106 a, 1106 b may be formed by etching the dielectric coverfilm bonded to the electrically conductive element 1104 a, 1104 b. Inone aspect, at least one of the electrically insulative elements 1106 a,1106 b may be configured as a spacer to provide a predetermined gapbetween upper and lower electrodes.

The electrically conductive elements 1104 a, 1104 b each compriseselectrically conductive material such as copper, gold plated copper,silver, platinum, stainless steel, aluminum, or any suitableelectrically conductive biocompatible material, for example. One or morethan one of the electrically conductive elements 1104 a, 1104 b may beconfigured and arranged to define a conductive electrode.

B. Flexible Circuit Electrode Including Upper and Lower ElectrodesCoupled by Longitudinal Flexure Bearing

FIGS. 60-66 illustrate a flexible circuit electrode 1200 comprising aflexure bearing 1228, according to one aspect of the present disclosure.The flexure bearing 1128 connects upper and lower flat flexible circuitelectrodes 1200 a, 1200 b that are spaced apart longitudinally relativeto the flexure bearing 1228.

FIG. 60 is a perspective view of a flexible circuit electrode 1200comprising upper and lower electrodes 1200 a, 1200 b coupled by aflexure bearing 1228 in an open configuration, according to one aspectof the present disclosure. FIG. 61 is another perspective view of theflexible circuit electrode 1200 shown in FIG. 60, according to oneaspect of the present disclosure.

FIG. 62 is a plan view of the flexible circuit electrode 1200 shown inFIG. 60, according to one aspect of the present disclosure. FIG. 63 is aplan view of the flexible circuit electrode 1200 shown in FIG. 60,according to one aspect of the present disclosure.

FIG. 64 is a side elevation view of the flexible circuit electrode 1200shown in FIG. 60, according to one aspect of the present disclosure.FIG. 65 is an elevation view of the flexible circuit electrode 1200shown in FIG. 60 taken from a distal end 1212, according to one aspectof the present disclosure. FIG. 66 is an elevation view of the flexiblecircuit electrode 1200 shown in FIG. 60 taken from a proximal end 1214,according to one aspect of the present disclosure.

With reference now to FIGS. 60-66 the flexible circuit electrode 1200comprises two separate electrodes, an upper flexible electrode 1200 aand a lower flexible electrode 1200 b that are coupled by a flexurebearing 1228 connecting the two electrodes 1200 a, 1200 b. The flexiblecircuit electrode 1200 comprises a lead 1202 for connecting the upperand lower electrodes 1200 a, 1200 b to an energy source, such, forexample, a radio frequency (RF) generator that outputs enough power toseal tissue. The long lead 1202 enables the upper and lower electrodes1200 a, 1200 b to be connected to the energy source at the handleportion of the electrosurgical device. A shorter longer lead may beprovided where it is desirable to connect the electrodes 1200 a, 1200 bto an energy source near the distal end of the end effector.

The upper electrode 1200 a can be attached to the upper jaw member andthe lower electrode 1200 b can be attached to the lower jaw member of aclamp jaw assembly of the electrosurgical instrument, for example. Theupper electrode 1200 a comprises an electrically conductive element 1204a that includes electrically insulative elements 1206 a (e.g.,insulative rings to establish desired gaps between electrodes in bipolarelectrosurgical instruments) and the lower electrode 1200 b comprises anelectrically conductive element 1204 b that includes electricallyinsulative elements 1206 b provided thereon. The electrically insulativeelements 1206 a, 1206 b prevent the electrically conductive elements1204 a, 1204 b from electrically shorting when the jaw members are in aclosed configuration. The electrically insulative elements 1206 a, 1206b may be made of a dielectric material, which may be coated with anonstick material such as TEFLON. The electrically conductive elements1204 a, 1204 b comprise electrically conductive materials such ascopper, gold plated copper, silver, platinum, stainless steel, aluminum,or any suitable electrically conductive biocompatible material, forexample.

Each of the upper and lower flexible circuit electrodes 1200 a, 1200 bfurther comprise knife slots 1208 a, 1208 b. The knife portion of theelectrosurgical instrument 2 (FIG. 1A) is slidably movable within theknife slots 1208 a, 1208 b to cut the tissue after it has been sealedusing electrosurgical energy. The flat flexible circuit electrodes 1200a, 1200 b each define a knife slot 1208 a, 1208 b and extends along alength of the electrode 1200. Although generally speaking the knifeslots 1208 a, 1208 b are laterally centered, this is not necessarilyalways the case, and in other aspects, the knife slots 1208 a, 1208 bmay be laterally offset from center.

The electrically insulative elements 1206 a, 1206 b of the flexiblecircuit electrode 1200 a, 1200 b are formed of electrically insulativematerials such as a polymer and more specifically can be an electricallyinsulative material (e.g., polyimide, polyester, fluorocarbon, or anypolymeric material, or any combinations thereof). The electricallyinsulative elements 1206 a, 1206 b are generally attached to the tissuecontacting side of the upper or lower jaw members of the clamp jawassembly.

The flexible circuit electrode 1200 utilizes the flexible nature of theflexible-circuit electrode manufacturing technology to incorporate avariety of lead lengths and active/passive components in the electrodecircuit. Exploiting the flexibility of configuration and potential costsavings of utilizing flexible circuits for bipolar electrodes 1200 a,1200 b.

The flexible circuit electrode 1200 can be configured in a variety ofways. In one aspect, the length of the lead 1202 can be short, i.e.,near the flexure bearing 1228 connecting the upper and lower electrodes1200 a, 1200 b and enabling replaceable electrodes 1200 a, 1200 b and/orjaws. The length of the lead 1202 can be long, moving the terminationpoint to the handle assembly of the electrosurgical instrument, reducingpart count, electrical connection points, and enabling the inclusion ofadditional active components such as switches, EEPROM, etc. intimatelyassociated with the upper and lower electrodes 1200 a, 1200 b.

In one aspect, an electrically insulative layers 1205 a, 1205 b may beprovided on the electrically conductive elements 1204 a, 1204 b toprevent electrically shorting the electrically conductive elements ofthe jaw member electrodes when they are in a closed configuration. Inanother aspect, the electrically insulative layers 1205 a, 1205 b defineelectrically insulative elements 1206 a, 1206 b to establish apredetermined gap between the jaw electrodes of a bipolarelectrosurgical instrument. In yet another aspect, the electricallyinsulative layers 1205 a, 1205 b may be configured as an electricallyinsulative cover that further defines the electrically conductiveelements 1204 a, 1204 b and can act as a spacer. The electricallyinsulative elements 1206 a, 1206 b may be defined by the electricallyinsulative layers 1205 a, 1205 b and can be configured as anelectrically insulative barrier between the jaw electrodes, provide apredetermined gap between the jaw electrodes, and/or assist tissuegrasping between the jaw electrodes. In one aspect, the electricallyinsulative elements 1206 a, 1206 b may comprise a nonstick coating ormay be formed of a nonstick material such as TEFLON to prevent tissuefrom sticking thereto. In one aspect, the electrically insulativeelements 1206 a, 1206 b may be formed of a dielectric material.

In one aspect, the electrically insulative layers 1205 a, 1205 b may beformed by bonding a dielectric cover film on the electrically conductiveelement 1204 a, 1204 b. In one aspect, the electrically insulativeelements 1206 a, 1206 b may be formed by etching the dielectric coverfilm bonded to the electrically conductive element 1204 a, 1204 b. Inone aspect, at least one of the electrically insulative elements 1206 a,1206 b may be configured as a spacer to provide a predetermined gapbetween upper and lower electrodes.

The electrically conductive elements 1204 a, 1204 b each compriseselectrically conductive material such as copper, gold plated copper,silver, platinum, stainless steel, aluminum, or any suitableelectrically conductive biocompatible material, for example. One or morethan one of the electrically conductive elements 1204 a, 1204 b may beconfigured and arranged to define a conductive electrode.

VII. Vacuum Formed Flexible Circuit Electrodes

FIGS. 67-69 illustrate a vacuum formed flexible circuit electrode 1300,according to one aspect of the present disclosure. FIG. 67 is aperspective view of an end effector 1330 comprising a vacuum formedflexible circuit electrode 1300, according to one aspect of the presentdisclosure. The end effector 1330 comprises an upper jaw 1320 a and alower jaw 1320 b. The upper and lower jaws 1320 a, 1320 b each maycomprise vacuum formed flexible circuit electrode 1300. The end effector1330 comprises a knife slot 1308. The upper jaw 1320 a is movable froman open position to a closed position and vice-versa relative to thelower jaw 1320 b.

FIG. 68 is a vacuum formed flexible circuit electrode 1300 disposed overa insert molded support 1312 or jaw 1320 b, according to one aspect thatcan be inserted in an injection molding tool, according to one aspect ofthe present disclosure. FIG. 68 is another view of the vacuum formedflexible circuit electrode 1300 shown in FIG. 68, according to oneaspect of the present disclosure. The vacuum formed flexible electrode1300 comprises an electrical conductive element 1304 disposed over aflexible circuit substrate 1306 which is placed over an insert moldedsupport 1312 or the jaw 1320 b.

In one process, the vacuum formed flexible circuit electrode 1300 can beincorporated with the lower jaw 1320 b, or the upper jaw 1320 a (FIG.67). First, the flexible circuit 1300 is vacuum formed to create adesired profile. That profile is then placed in an injection moldingtool to create a substrate to support that shape. The flexible circuitelectrode 1300 is then trimmed and the assembly is bonded to a jaw 1320a, 1320 b by an adhesive, a second overmold step, or some othertechnique. A first manufacturing process can be carried out inaccordance with the following steps:

Step 1—vacuum form flexible circuit to create a desired profile;

Step 2—place profile in an injection molding tool to create a substrateto support that shape;

Step 3—Trim the flexible circuit;

Step 4—Bond the flexible circuit to a jaw with adhesive, secondovermold, or other technique.

In another process, the vacuum formed flexible circuit electrode 1300 isvacuum formed, trimmed, and then adhered directly to the lower jaw 1320b, or the upper jaw 1320 a (FIG. 67), of the end effector 1330 (FIG. 67)jaw assembly, via adhesive, insert molding, or some other technique. Inthis aspect, the jaw 1320 a, 1320 b would have a complimentary profileto support the flexible circuit electrode 1300 profile. A secondmanufacturing process can be carried out in accordance with thefollowing steps:

Step 1—vacuum form the flexible circuit;

Step 2—trim the flexible circuit;

Step 3—Adhere the flexible circuit directly to the jaw with adhesive,insert mold, or other technique.

VIII. Comparison of Thin Flexible Circuit Electrodes and ThickConventional Electrodes

FIGS. 70-72 illustrate a comparison of a thin, copper flexible circuitelectrode 1400 and a conventional stainless steel electrode 1430 fromthe standpoint of self-heating, according to one aspect of the presentdisclosure.

FIG. 70 illustrates a flexible circuit electrode 1400, according to oneaspect of the present disclosure. The flexible circuit electrode 1404comprises a lead 1402 to attach an electrically conductive element 1404,which defines the electrode tissue sealing surface, to an energy source.The electrode 1404 also comprises a plurality of electrically insulativeelements 1406 (e.g., electrically insulative elements to establishdesired gaps between electrodes in bipolar electrosurgical instruments).A knife slot 1408 is provided as a channel for a knife to translatealong the slot 1408. An insulative element, not shown, is bonded to theopposite side of the electrically conductive element 1404.

In one aspect, the flexible circuit electrode 1400 may be implementedwith the following dimensions:

R=0.097″, where R is the radius of curvature of the distal end 1412 ofthe electrode 1400;

d1=0.036″, where d1 is the width of the knife slot 1408;

d2=0.823″, where d2 is the length of the straight portion of the 1400 tothe end of the lead 1402.

FIG. 71 illustrates a flat conductive trace 1420 for a flexible circuitelectrode, according to one aspect of the present disclosure. The flatconductive trace 1420 includes a dielectric insulator layer 1422 havinga thickness d3=0.0020″, a gold plated copper layer 1424 having athickness d4=0.0028″, and an electrically insulative layer 1426 (e.g.,polyimide, polyester, fluorocarbon, or any polymeric material, or anycombinations thereof) having a thickness d5=0.0050″. The trace 1420 hasa width d6=0.1560″ and a length of d7=4.2274″.

FIG. 72 is a comparison of a conventional stainless steel electrode 1430versus the thin copper flexible circuit electrode 1420, according to oneaspect of the present disclosure.

With reference now to FIGS. 70-72, in one aspect the flexible circuitelectrode 1400 may be configured to reduce the self-heating of theelectrode 1400 and allow the majority of the heat to be generated by theself-heat of the tissue. The superiority of using a thin copperconductor over thicker steel or stainless steel conductor will now bedemonstrated.

The total resistance of a conductor is greater for alternating currentthan it is for continuous current due to induced EMFs (electromotiveforces.) These forces are greater at the center of a conductor than theyare at the surface and they resist the flow of current. This results inthe current density to be greater at the surface of a conductor than atthe center. This current density variation is referred to as the skineffect.

Several factors contribute to the skin effect and will subsequentlyaffect the total resistance of a conductor. The conductor's resistivityvalue (ρ), frequency (f), and relative permeability (μ) can be used toestimate the skin depth, where the skin depth is the distance from thesurface of a conductor in which the current density is reduced to 1/e ofthe current density at the conductor's surface (approximately 37%.)Approximately 98% of the current moving in a conductor will be limitedto the area defined by 4 times the skin depth.

For wires, tubes, and other compact shapes the skin depth (δ) can beapproximated by Equation 1:

$\begin{matrix}{\delta = {\frac{1}{2\pi}\sqrt{\frac{10^{7}\rho}{f\; \mu_{r}}}}} & \left( {{Eq}.\mspace{11mu} 1} \right)\end{matrix}$

Table 1 provides material properties for some common materials:

Table 1: Properties of common materials

TABLE 1 p (Ω · m) Material at 20° C. Relative Permeability (μ_(r))Silver 1.59 × 10−8 0.999974 Copper 1.68 × 10−8 0.999991 Gold 2.44 × 10−80.999998 Aluminum 2.82 × 10−8 1.000022 Tungsten 5.60 × 10−8 1.000068Molybdenum   5 × 10−8 1.000123 Nickel 6.99 × 10−8 100-600 Lithium 9.28 ×10−8 1.000014 Iron 1.00 × 10−7   6000-2000000 Platinum 1.06 × 10−71.000265 Carbon steel (1010) 1.43 × 10−7 100 Titanium 4.20 × 10−71.000182 Stainless steel 6.90 × 10−7 1.003 to 7 (Austenitic 40-135(Martensitic hardened) 750-950 (Martensitic annealed) 1000-1800(Ferritic)

Generally speaking the resistance of a conductor can be calculated byusing Equation 2.

$\begin{matrix}{R = \frac{Lx\rho}{A}} & \left( {{Eq}.\mspace{11mu} 2} \right)\end{matrix}$

where (L) is the length of the conductor, (ρ) is the resistivity and (A)is the area.

In the case where the current is confined to a small area near thesurface of the conductor (δ<<diameter), the subsequent resistance (R)can be estimated by Equation 3.

$\begin{matrix}{R \approx \frac{Lx\rho}{{\delta\pi}\; D}} & \left( {{Eq}.\mspace{11mu} 3} \right)\end{matrix}$

where (τD) is the perimeter of a round conductor.

Typical Stainless Steel (assuming Austenitic) electrodes vs. flexiblecircuit electrodes self-heat performance. One of the significant factorsin electrode material and geometry selection is the propensity toself-heat when current is passed through them. Table 2 showscalculations for a typical stainless steel electrode compared to a flexcircuit electrode that has the same tissue contact area butsignificantly less cross-sectional area.

TABLE 2 Conventional Electrode Frequency 330000 Electrode 1 LengthElectrode 0.2 Width Electrode 0.01 Height Current 3 Relative Reference ρ(Ω · m) at Permeability for a 37% Depth, 98% Depth, Power from Material20° C. (μ) range inches inches Resistance Electrode Silver 1.59E−080.999974 0.004352749 0.017410995 0.001826432 0.016437889 Copper 1.68E−080.999991 0.004474206 0.017896824 0.001877428 0.016896853 Gold 2.44E−080.999998 0.00539206 0.021568241 0.002262586 0.020363274 Aluminum2.82E−08 1.000022 0.005 0.023186711 0.002432428 0.02189185 Tungsten5.60E−08 1.000068 0.008168431 0.032673723 0.003427831 0.030850479Molybdenum 5.00E−08 1.000123 0.007718229 0.030872917 0.0032390850.029151764 Nickel 6.99E−08 100-600 100 9.13E−04 0.003650547 0.0382956290.344660662 Lithium 9.28E−08 1.000014 0.01051551 0.042062039 0.004412530.039712768 Iron 1.00E−07  6000-200000 6000 1.41E−04 0.0005636940.354802153 3.193219373 Platinum 1.06E−07 1.000265 0.0112371140.044948455 0.004716514 0.042448622 Carbon Steel 1.43E−07 1000.001305351 0.005221405 0.054774527 0.492970747 (1010) Titanium 4.20E−071.000182 0.022368894 0.089475576 0.009388037 0.084492331 Stainless6.90E−07 1 0.028673713 0.114694851 0.012031926 0.108287337 SteelStainless 6.90E−07 7 0.010837645 0.043350579 0.031833485 0.286501365Steel Stainless 6.90E−07 _0-135 40 4.53E−03 0.018134848 0.0760965840.684869256 Steel (Martenstitic hardened) Stainless 6.90E−07  50-950 7501.05E−03 0.004188064 0.329507875 2.965570872 Steel (Martenstiticannealed) Stainless steel 6.90E−07 1000-1800 1000 9.07E−04 0.003626970.38048292 3.424346282 (Ferritic) One Aspect Of A Proposed FlexElectrode Electrode 1 Length Electrode 0.2 Width Electrode 0.0028 HeightCopper 1.68E−08 0.999991 4.47E−03 0.017896824 6.71E−03 0.060345902Stainless steel 6.90E−07 7 0.010837645 0.043350579 1.14E−01 1.023219161% Difference 4007% 600% 142% 142% 1596% 1596% For Same Geometry

A comparison of a conventional stainless steel electrode 1430 with across-section of 0.2×0.1″ and a copper electrode 1420 with across-section of 0.2×0.0028″. Assuming a 1″ length and 3 A of currentflowing (arbitrary) at a typical electrosurgical frequency of 330 kHz,the relative self-heat of the two designs are compared. The resultsindicate that the copper electrode 1420, even though the cross-sectionis significantly less, exhibits less self-heating than the thickerstainless steel electrode 1430. Accordingly, based on these results, onecan conclude that the copper electrode 1420 in a flexible circuitarrangement is superior to a conventional stainless steel electrode1430. Although, copper may be determined to be a sub-optimal choice forbiocompatibility, the copper conductor can be clad or coated withanother biocompatible material such as gold.

Table 3 shows the relative self-heat power of a conventional steelelectrode vs. a flat copper flex electrode.

TABLE 3 Conventional Steel Electrode vs. Flat Copper Flex ElectrodeRelative self-heat power from 0.2 × 0.1 Steel 0.29 Electrode Relativeself-heat power from Flat 0.2 × 0.0028 Copper 0.06 Flex Electrode

IX. Flexible Circuit Electrode Manufacturing Process A. Mass ProducedCost Effective Flexile Circuit Electrode Sub-Assembly IncludingInsulative Barrier and Non-Conductive Stand-Offs

FIGS. 73-80 illustrate a mass produced and cost effective flexilecircuit electrode sub-assembly including insulative barrier andnon-conductive stand-offs, according to one aspect of the presentdisclosure.

FIG. 73 is a perspective view of an assembly 1500 comprising an array1502 of flexible circuit electrodes 1504, according to one aspect of thepresent disclosure. FIG. 74 is an elevation view of the assembly 1500shown in FIG. 73, according to one aspect of the present disclosure.

FIG. 75 is a detail plan view of the assembly 1500 shown in FIG. 73showing individual flexible circuit electrodes 1504 fixed in a carrierweb 1506 prior to die cutting, according to one aspect of the presentdisclosure. In one aspect, the carrier web 1506 may comprise fused linksthat are can be activated to sever the individual flexible circuitelectrodes 1504 from the assembly 1500.

With reference to FIGS. 73-75, the following disclosure provides atechnique of mass producing electrode assemblies 1500 for a bipolarmedical device electrode 1504. In this assembly 1500 the final electrode1504 is bonded to an electrically insulative backing material (e.g.,polyimide, polyester, fluorocarbon, or any polymeric material, or anycombinations thereof) and insulative elements are printed at two or morelocations on the tissue sealing surface of the electrode 1504. Theseelements serve to prevent the electrode from shorting with the opposingjaws and serve to maintain a defined gap between the upper and lowerelectrodes.

The electrodes 1504 can be mass produced by laminating a metallic sheetto an electrically insulative film. Then the insulative elements arescreen printed on the conductive face of the electrode. The shape of theelectrode 1504 is formed by screen printing a protective barrier on themetallic film. This protective barrier allows the shape of the electrodeto be formed by photoetching away the remaining material which does notmake up the final shape of the electrode 1504. Finally, individualelectrodes 1504 are die-cut out leaving electrode subassemblies that canbe bonded to the jaws of the end effector. The electrically insulativebacking material or barrier can have an adhesive or a brazeable surfaceon the back side of the electrically insulative backing material toallow for attachment to the lower or upper jaw depending on the devicejaw construction.

With reference to FIGS. 76-80, FIG. 76 is a perspective view of anassembly 1600 comprising an array 1602 of flexible circuit electrodes1604 in a carrier web 1606, according to one aspect of the presentdisclosure. FIG. 77 is a detail view of the array 1602 of the flexiblecircuit electrodes 1604 in a carrier web 1606 shown in FIG. 76,according to one aspect of the present disclosure.

FIG. 78 is an individual flexible circuit electrode 1604 sub-assembly ina carrier web 1606 prior to die-cutting, according to one aspect of thepresent disclosure. FIG. 79 is a detail view of the individual flexiblecircuit electrode 1604 sub-assembly in a carrier web 1606 shown in FIG.78, according to one aspect of the present disclosure.

FIG. 80 is an individual flexible circuit electrode 1604 sub-assemblyshown in FIG. 78 after die cutting and ready to be bonded to a jaw of anend effector, according to one aspect of the present disclosure. Theelectrode 1604 comprising an electrically conductive metal layer 1620,an electrically insulative layer 1606 (e.g., polyimide, polyester,fluorocarbon, or any polymeric material, or any combinations thereof)attached to one side of the conductive metal layer 1620. Dielectricinsulative elements 1610 are printed on the tissue contacting surface1616 of the conductive metal layer 1620. In one aspect, the dielectricinsulative layer 1612 can be printed on the lead 1618 portion of theelectrode 1604. A knife slot 1614 is provided in the electrode 1604 toreceive the knife through the slot.

The following disclosure provides a technique of mass producingelectrode assemblies 1600 for the bipolar medical device electrode 1604.In this assembly 1600 the final electrode 1604 is bonded to anelectrically insulative backing 1606 (e.g., polyimide, polyester,fluorocarbon, or any polymeric material, or any combinations thereof)and insulative elements 1610 are printed at two or more locations on thetissue sealing surface 1616 of the electrode 1604. These elements 1610serve to prevent the electrode 1604 from shorting with the opposing jawsand serve to maintain a defined gap between the upper and lowerelectrodes. The dielectric insulative layer 1612 used to print theelements 1610 can also be printed onto the lead portion 1618 of theelectrode 1604.

The electrodes 1604 can be mass produced by laminating a metallic sheet1620 to an electrically insulative film 1606 (e.g., polyimide,polyester, fluorocarbon, or any polymeric material, or any combinationsthereof). Then the insulative elements 1610 are screen printed on theconductive face 1616 of the electrode 1604. The shape of the electrode1604 is formed by screen printing a protective barrier on the metallicfilm 1620. This protective barrier allows the shape of the electrode tobe formed by photoetching away the remaining material which does notmake up the final shape of the electrode 1604. Finally, individualelectrodes 1604 are die-cut out leaving electrode subassemblies that canbe bonded to the jaws of the end effector. The electrically insulativebarrier (e.g., polyimide, polyester, fluorocarbon, or any polymericmaterial, or any combinations thereof) can have an adhesive or abrazeable surface on the back side of the polyimide barrier to allow forattachment to the lower or upper jaw depending on the device jawconstruction.

B. Flow Diagram of Process of Manufacturing Flexible Circuit Electrodes

FIG. 81 is a flow diagram 1700 of a process of manufacturing flexiblecircuit electrodes, according to one aspect of the present disclosure.An electrically conductive sheet is laminated 1702 to an electricallyinsulative sheet. The electrically conductive sheet may be a sheet madeof copper, a gold plated copper, silver, platinum, stainless steel,aluminum, or any suitable electrically conductive biocompatiblematerial, for example. The electrically insulative sheet may be a sheetof electrically insulative material (e.g., polyimide, polyester,fluorocarbon, or any polymeric material, or any combinations thereof).

An electrode is then formed 1704 on the electrically conductive sheetaccording to a predetermined pattern. This process may include forexample etching an electrode on the electrically conductive sheet. Inone aspect, a desired pattern may be formed by screen printing aprotective barrier to the electrically conductive sheet. This protectivebarrier allows the shape of the electrode to be formed by photoetchingaway the remaining material which does not make up the final shape ofthe electrode.

Once the electrode is formed, electrically insulative elements areprinted 1706 of the tissue contacting surface of the electrode. Theelectrically insulative elements may be formed of a dielectric materialthat can be screen printed on the tissue contacting surface of theelectrode. The electrically insulative elements (e.g., insulativeelements to establish desired gaps between electrodes in bipolarelectrosurgical instruments).

Once the electrically insulative elements are printed on the tissuecontacting surface of the electrode, the individual electrode areseparated 1708 from the electrically insulative and conductive sheetsthat act as a web to hold the individual electrode elements in placeduring the processing phase. In one aspect, separating the electrodescomprises die cutting the electrodes, they can be attached to the jawsof the upper and/or lower electrode.

In accordance with the present disclosure, electrically insulativematerials, such as dielectric materials, may be applied to a variety offlexible substrates by screen printing, stamping, dip coating, syringedispensing, spraying, and/or pad printing, or combinations thereof.Suitable flexible substrates may include, without limitation, Kapton,Mylar, epoxy/glass, polycarbonate, treated and untreated polyester,glass, sputtered surfaces, Aluminum, and/or combinations thereof.

X. Thermal Assist for Advanced RF Electrodes

FIGS. 82-87 describe a thermal assist end effector, according to oneaspect of the present disclosure. FIG. 82 is a perspective view of anend effector jaw assembly 1800 comprising an electrode 1802 and athermal assist heater 1804, according to one aspect of the presentdisclosure. The end effector jaw assembly 1800 also comprises a thermaland electrical insulator 1806. The resistive thermal heater 1804 is inthe form of a foil attached to the to the electrode 1802. Use of theresistive thermal heater 1804 can reduce the time spent the lowimpedance (|Z|), high power, portion of the sealing cycle, that resemblea “bathtub” shape. Currently, when impedance is extremely low, the RFgenerator is limited in the power that can be transferred to the tissueelectrically. By transferring power thermally to the tissue using theresistive thermal heater 1804, the tissue can be desiccated which willallow the cycle to finish more quickly. The resistive thermal heater1804 foil can be integrated with the metal electrode or with a flexiblecircuit electrode 1802 as shown in FIG. 82.

Low impedance (|Z|) loads can cause long cycle sealing times. This isbecause the generator is limited in powering low |Z| loads. Thegenerator or instrument can sense when the load is below a thresholdwhere the generator is able to apply sufficient power to make a moderatecycle time. When this occurs, the resistive thermal heater 1804 can beturned on to give the tissue a boost into the coagulation cycle.

Once the power delivery from the generator is sufficient, then theresistive thermal heater 1804 can be turned off and the RF energydelivered by the generator can completed the seal. A threshold for thelow impedance can be set such that when the generator cannot deliver 50W or more of power then the resistive thermal heater 1804 heater isturned on. In one example, 3.5 A may be the maximum current availablefrom a generator. Based on conventional power formulas P=I²R andR=50/35²≅4 Ohms. Once the generator is able to deliver ˜200 W, then theresistive thermal heater 1804 can be turned off. In the above example,this is ˜=16 Ohms.

Minimizing or reducing the time spent in the “bathtub” portion of thecycle will reduce the overall tissue sealing cycle time. Activation anddeactivation of the thermal assist can be accomplished in several wayswith varying benefits and trade-offs, some of which include atemperature based closed-loop control usingperipheral-integral-derivative (PID) or other technique. A specifictemperature-time profile is applied to the tissue while sensing tissuetemperature or predicting tissue temperature based on jaw temperature. Atime based control can be used to control thermal power applied for apredetermined period of time to assist in transitioning the bathtub.temperature control using a bi-metal “thermostat” switch can be used tode-energize the thermal assist when a specific temperature has beenachieved. An RF performance feedback technique can be used where thegenerator is employed to detect when impedance is too low to effectivelydrive current into the tissue, activating the thermal assist. Whenimpedance rises, deactivating the thermal assist to rely on Advanced RF.

FIG. 83 is a graphical depiction 1810 of power, voltage, and currentversus impedance, according to one aspect of the present disclosure.Power (P), voltage (V) and current (I) are depicted along the verticalaxis and impedance (R) is depicted along the horizontal axis. As shown,wen the impedance (R) is low or near zero, current (I) is high or at itsmaximum and voltage (V) and power (P) are at their minimum or zero. Asthe impedance increases to right along the horizontal axis, current (I)gradually decreases and the power (P) and voltage (V) increase. As theimpedance (R) increases further, the current (I) and power (P) drop tonear zero and the voltage stabilizes to a maximum.

FIG. 84 is a schematic of a circuit 1820 of an RF energy source 1822with a low impedance load between two electrodes 1826 a, 1826 b,according to one aspect of the present disclosure. The circuit 1820 is aconventional RF energy sealing circuit where an RF energy source 1822 iselectrically coupled to first and second electrode 1826 a, 1826 b withtissue 1824 located therebetween. When the moisture content of thetissue 1824 positioned between the electrodes 1826 a, 1826 b is high,the impedance of the tissue is low. Accordingly, the RF energy source1822 will output a high current. As RF energy is applied to the tissue1824 moisture is driven out of the tissue due to the heating effect ofthe RF energy applied to the tissue 1824. As moisture is driven out ofthe tissue 1824, the tissue 1824 desiccates and the impedance increases,which reduces the amount of current through the tissue 1824. The processcontinues until the impedance reaches a predetermined quantity.

FIG. 85 is a schematic of a circuit 1830 comprising an RF energy source1822 with a low impedance load between the electrodes 1826 a, 1826 b, aheater energy source 1832 with a heater 1834, and a thermal assistcontrol circuit 1831, according to one aspect of the present disclosure.As shown, the circuit 1830 comprises an RF circuit comprising an RFenergy source 1822 for driving the electrodes 1826 a, 1826 b and acontrol circuit 1836 to monitor tissue impedance |Z_(T)| and control theRF energy source 1822 based on the measured impedance. The circuit 1830also comprises a thermal assist control circuit 1831 comprising a heaterenergy source 1832 to drive the heater 1834 attached to one of theelectrodes 1826 a and a heater control circuit 1838 to control theheater energy source 1832 based on inputs from the RF control circuit1836. The heater energy source 1832 applies energy to the heater 1834,which in turn heats the tissue to assist the RF energy source 1822during low impedance load periods. The RF control circuit 1836 can turnthe RF source ON and OFF and can send an instruction or a signal to theheater control circuit 1838, which can turn the heater source ON andOFF. The thermal assist control circuit 1831 powering the heater 1834can be a single system that applies about 50 W to about 100 W of powerthrough a battery, a separate mains supplied source, or from thegenerator output. See 2015/0190189, for example.

FIG. 86 is a graphical depiction 1840 of impedance (|Z|) 1844 and power(P) 1842 versus time (t), according to one aspect of the presentdisclosure. Impedance (|Z|) 1844 and power (P) 1842 are depicted on thevertical axis and time (t) is depicted on the horizontal axis. Withreference also to FIG. 85, as the tissue 1824 impedance (|Z|) 1844varies, the power (P) 1842 delivered to the tissue 1824 also varies.When the tissue impedance (|Z|) 1844 drops below a low impedancethreshold Z_(L) the heater control circuit turns ON 1846 the heater 1834to apply heat to the tissue 1824. When the tissue impedance (|Z|) 1844rises above a high impedance threshold Z_(H) the heater control circuitturns OFF 1848 the heater 1834.

FIG. 87 is logic flow 1850 depicting a process for operating the thermalassist control circuit 1831 shown in FIG. 85, according to one aspect ofthe present disclosure. With reference also to FIGS. 85 and 86, afterthe surgeon grasps tissue between the jaws of the end effector RF energyis applied 1852 to the electrodes 1826 a, 1826 b. During the process thecontrol circuit 1836 monitors the tissue impedance |Z_(T)| and compares1854 it to predetermined thresholds. When the tissue impedance |Z_(T)|is less than the low tissue impedance threshold Z_(L) the heater controlcircuit 1838 turns ON 1856 the heater 1834, otherwise the RF coagulationcycle is completed 1862. The control circuit 1836 continues comparing1858 the measured tissue impedance to the predetermined thresholds. Whenthe tissue impedance |Z_(T)| is less than the high tissue impedancethreshold Z_(H) the heater 1834 stays on until the tissue impedance|Z_(T)| is greater than the high tissue impedance threshold Z_(H) andthen the heater control circuit 1838 turns OFF 1860 the heater 1834 andcompletes 1862 the RF coagulation cycle.

The instrument and the generator can be configured to execute most anyRF algorithm. One jaw algorithm is described in U.S. Pat. No. 9,060,776,for example.

XI. Optical Force Sensing for RF Sealing Process Monitoring

FIGS. 88-91 illustrate an optical force sensor 1900 based on measuringlight transmission through micro-bent polymer optical fibers 1902 (POF)embedded in an elastomer strip 1904, according to one aspect of thepresent disclosure.

FIG. 88 is an optical force sensor 1900 in a relaxed state, according toone aspect of the present disclosure. FIG. 89 is a cross section of theoptical force sensor 1900 shown in FIG. 88 in a relaxed state, accordingto one aspect of the present disclosure.

FIG. 90 is a cross section of the optical force sensor 1900 shown inFIG. 88 in a compressed state, according to one aspect of the presentdisclosure. FIG. 91 is a simplified schematic diagram of the opticalforce sensor 1900 shown in FIG. 88, according to one aspect of thepresent disclosure.

With reference now to FIGS. 88-91, this technique employs a force sensor1900 based on measuring light transmission through micro-bent polymeroptical fibers 1902 (POF). This technique provides improved flexibilityof RF sealing algorithms to accommodate the variety of tissue propertiesand behavior encountered in practice. This technique also reduces thevariability and improve strength of vessel seals by controlling theapplied compressive force. The advantage of using an optical sensor isthat it is undisturbed by RF fields. The advantage of POFs 1902 is thatthey are inexpensive and more flexible than silica optical fibers.

The sensor 1900 comprises a POF 1902 set in an elastomer strip 1904. Theelastomer strip 1904 has a wavy shape while the fiber inside isstraight, as shown in section view in FIG. 89. When the sensor 1900 iscompressed between two flat surfaces 1906, 1908, as shown in FIG. 90,the POF 1902 is deformed into a series of micro-bends. When the POF 1902is bent part of the light escapes from it. With the increase ofcompression force 1910 the deformation of the sensor 1900 elastomerstrip 1904 varies and the light transmitted through the POF 1902decreases monotonically. Thus the attenuation of transmitted light is ameasure of the applied force 1910.

As shown in FIG. 91, the sensor 1900 is interrogated by sending lightfrom an LED 1912 through a POF 1902 to the sensor strip 1904. The lightreturning from the strip 1904 is measured by a photodiode 1914. Anotherphotodiode 1916 measures a fraction of the light from the LED 1912carried by a POF 1918 coupled with the POF 1902 bringing light to thesensor 1900. The ratio of the signals from the two photodiodes 1914,1916 can be calibrated versus the applied force 1910. The sensor 1900can be inserted between the electrode and the jaw of an RF device suchas an electrosurgical instrument 2 shown in FIG. 1A to monitor theapplied force 1910.

XII. Polymer Optical Fiber (POF) on Flexible Circuit Electrode

FIGS. 92-93 illustrate polymer optical fibers (POF) integrated withflexible circuit electrodes for sensing a pressure in a jaw of an endeffector 2000, according to one aspect of the present disclosure. FIG.92 is a section view of a lower jaw 2002 of the end effector 2000comprising a POF force sensor 2004, according to one aspect of thepresent disclosure.

Turning now to FIG. 92, the POF force sensor 2004 is disposed on thelower jaw 2002 of the end effector 2000. The POF force sensor 2004comprises first and second layers of electrically insulative film 2010,2012, (e.g., polyimide, polyester, fluorocarbon, or any polymericmaterial, or any combinations thereof), such as Kapton, for example. Aflexible electrode 2014 is located below the first electricallyinsulative film 2010. The lower side of the flexible electrode 2014comprises a first plurality of trace layer segment conductors 2016. Theupper of the second electrically insulative film 2012 comprises a secondplurality of trace layer segment conductors 2018. Polymer optical fibers2008 are integrated with the flexible electrode 2014 between the firstand second plurality of the trace layer segment conductors 2016, 2018.Accordingly, the POF 2008 is located between what would otherwise betrace layer segments 2016, 2018 of the flexible electrode. The tracelayer segment conductors 2016, 2018 are printed in an offset pattern asshown in FIG. 92, which causes the POF 2008 to bend when pressure isapplied to the flexible electrode 2014. The flexible electrode 2014configuration of the POF force sensor 2004 enables a pressure profilefeedback from the end effector 2000 to be processed in the surgicalinstrument handle or electrosurgical generator.

FIG. 93 is a section view of the end effector 2000 shown in FIG. 92 withtissue 2020 disposed on the POF force sensor 2004, according to oneaspect of the present disclosure. As the upper jaw (shown for clarity ofdisclosure) closes on the tissue 2020 and applies a force on the tissue2020 against the lower jaw 2002, micro bends 2022 are developed in thePOF 2008 layer. The POF force sensor 2004 is based on measuring lighttransmission through the micro bends 2022 of the POF 2008 layer. Thistechnique provides improved flexibility of RF sealing algorithm toaccommodate the variety of tissue properties and behavior encountered inpractice. The POF force sensor 2004 also reduces the variability andimproves the strength of vessel seals by controlling the appliedcompressive force. The POF force sensor 2004 operates on principlessimilar to the optical force sensor 1900 based on measuring lighttransmission through micro-bent POF 1902 embedded in an elastomer strip1904, according to FIGS. 88-91.

The POF force sensor 2004 senses the pressure profile in the jaw 2002 aswell as the position of the tissue 2020. The pressure applied to thetissue 2020 and the location of the tissue 2020 in the jaws 2002 areparameters that effect sealing performance. Obtaining information aboutthe pressure profile in the jaws 2002 and the position of the tissue2020 allows the algorithm to be adjusted in real time according to howthe surgical instrument is being used and improves sealing performancedue to the device receiving pressure feedback from the end effector2000.

XIII. Flat Patterned Flexible Electrode Including Flexure Bearing

FIGS. 94-97 illustrate flat patterned flexible circuit electrodescomprising a flexure bearing, according to one aspect of the presentdisclosure. The flat patterned flexible circuit electrodes utilize theflexible nature of the flexible circuit electrode to incorporate aflexure bearing. This flat patterned flexible circuit electrodes enablesboth poles of the bipolar electrode to be fabricated in a singlecontiguous component. There are a variety of flat patterns which willallow the incorporation of both poles of a bipolar device into a singleflexible circuit. These designs can be configured to include a flexurebearing within the flexible circuit. The introduction of a bipolarelectrode consisting of a single flexible circuit enables a number ofunique configurations and features as described herein in connectionwith FIGS. 94-95 and FIGS. 96-97.

A. Flat Patterned Flexible Circuit Electrode where Upper and Lower JawElectrode Elements are in Transverse Orientation Relative to aLongitudinal Element

FIG. 94 is a flat patterned flexible circuit electrode 2100 in a flatstate where an upper jaw electrode element 2102 and a lower jawelectrode element 2104 are in transverse orientation relative to alongitudinal element, according to one aspect of the present disclosure.The flexible circuit 2100 comprises an upper jaw electrode element 2102,a lower jaw electrode element 2104, and a longitudinal element 2106 thatextends from the junction of the upper and lower jaw electrode elements2102, 2104 to a control circuit or a generator circuit. Electricallyconductive traces 2108 extend along the longitudinal element 2106 and inthe upper and lower jaw electrode elements 2102, 2104 to deliverelectrical energy to an end effector. The flexible circuit electrode2100 is manufactured in the flat state in a single contiguous componentas shown in FIG. 94 and is folded in the state shown in FIG. 95 whendisposed within the electrosurgical instrument.

FIG. 95 illustrates the flat patterned flexible circuit electrode 2100shown in FIG. 94 in a folded state where the upper and lower jawelectrode elements 2102, 2104 create a flexure bearing 2110, accordingto one aspect of the present disclosure. The flexible circuit electrode2100 is folded in the state shown in FIG. 93 when it is disposed withina surgical instrument. The upper jaw electrode element 2102 is disposedin the upper jaw of an end effector and the lower jaw electrode element2104 is disposed in the lower jaw of the end effector. The longitudinalelement 2106 is disposed within a shaft of the electrosurgicalinstrument. The flexure bearing 2110 provides the necessary flexure whenthe upper and lower jaws of the end effector open and close.

B. Flat Patterned Flexible Circuit Electrode where Upper and Lower JawElectrode Elements are in Parallel Orientation Relative to aLongitudinal Element

FIG. 96 is a flat patterned flexible circuit electrode 2120 in a flatstate where the upper and lower jaw electrode elements 2122, 2124 are inparallel orientation relative to a longitudinal element 2126, accordingto one aspect of the present disclosure. The flexible circuit 2120comprises an upper jaw electrode element 2122, a lower jaw electrodeelement 2124, and a longitudinal element 2126 that extends from thejunction of the upper and lower jaw electrode elements 2122, 2124 to acontrol circuit or a generator circuit. Electrically conductive traces2128 extend along the longitudinal element 2126 and in the upper andlower jaw electrode elements 2122, 2124 to deliver electrical energy tothe end effector. The flexible circuit electrode 2120 is manufactured inthe flat state in a single contiguous component as shown in FIG. 96 andis folded in the state shown in FIG. 97 when disposed within anelectrosurgical instrument.

FIG. 97 illustrates the flat patterned flexible circuit electrode 2120shown in FIG. 96 in a folded state where the upper and lower jawelements 2122, 2124 create a flexure bearing 2130, according to oneaspect of the present disclosure. The flexible circuit electrode 2120 isfolded in the state shown in FIG. 97 when it is disposed within ansurgical instrument. The upper jaw electrode element 2122 is disposed inthe upper jaw of an end effector and the lower jaw electrode element2124 is disposed in the lower jaw of the end effector. The longitudinalelement 2106 is disposed within a shaft of the electrosurgicalinstrument. The flexure bearing 2110 provides the necessary flexure whenthe upper and lower jaws of the end effector open and close.

XIV. Switching and Control A. Flexible Circuit Including an IntegratedSlider Switch to Control Switching Modes

FIGS. 98-99 illustrate a flexible circuit comprising an integratedslider switch to control switching modes, according to one aspect of thepresent disclosure. The flexible circuit can be located proximally in ahandle of an electrosurgical instrument and may contain a series ofconductive pads with conductive traces. When the conductive pads arebridged with a slider switch different functionality can be obtained. Inone aspect, the slider switch may be employed to switch between bipolarand monopolar RF operation.

FIG. 98 is a side elevation view of a flexible circuit electrode 2200comprising an integrated slider switch 2202, according to one aspect ofthe present disclosure. FIG. 99 is a plan view of the flexible circuitelectrode 2200 shown in FIG. 98 showing the integrated slider switch2202, according to one aspect of the present disclosure. With referencenow to FIGS. 98-99, the flexible circuit electrode 2200 can bepositioned proximally in a handle of an electrosurgical instrument. Theflexible circuit electrode 2200 comprises a series of conductive pads2204 a, 2204 b, 2206 a, 2206 b with conductive traces 2208 a, 2208 b,2210 a, 2210 b. When the conductive pads 2204 a, 2204 b, 2206 a, 2206 bare bridged with the contact 2218 of the slider switch 2202 differentfunctionality can be obtained. In one aspect, the slider switch 2202 maybe employed to switch between monopolar RF operation in a first position2214 shown in solid line where the return path is disconnected andbipolar RF operation shown in a second position 2216 shown in phantomline.

B. Selectively Addressable Flexible Circuit Electrode IncludingControlled Switching Areas and Switching Modes

FIGS. 100-102 illustrate various flexible circuit electrodeconfigurations including a controlled switching area to control variousswitching modes and enabling the flexible circuit electrode to beselectively turned on and off in different areas, according to oneaspect of the present disclosure. The flexible circuit electrode can beturned on and off in different areas to enable the inside and outsideportions of the end effector to be controlled separately. This enablescontrol of the current density through the width of the electrode. Otheraspects enable the distal electrode element to be used for touching uparound bleeding areas at the surgical site. Other aspects enable controlof the outside edges to enable touch up with the distal electrodeelement or allow the user to turn off the outer edges when operatingaround delicate structures.

FIG. 100 is a planar view of a flexible circuit electrode 2300configured to enable inner and outer segments 2302, 2304 of theelectrode 2300 to be controlled separately and independently, accordingto one aspect of the present disclosure. The flexible circuit 2300comprises a knife slot 2306 and an inner electrode 2302 and an outerelectrode 2304 surrounding the knife slot 2306. The inner and outerelectrodes 2302, 2304 are separately and independently controllable.Accordingly, the inner and outer electrodes 2302, 2304 can be separatelyand independently energized. This configuration enables the flexiblecircuit electrode 2300 to be turned on and off in different areas toenable the inner and outer segments 2302, 2304 of the flexible circuitelectrode 2300 to be controlled separately. This enables control of thecurrent density through the width of the flexible circuit electrode2300.

FIG. 101 is planar view of a flexible circuit electrode 2310 configuredto enable separate and independent control of a distal tip 2318 of theelectrode 2310, according to one aspect of the present disclosure. Theflexible circuit electrode 2310 comprises one electrode 2312 disposedalong lateral segments 2316 a, 2316 b of a jaw of an end effectorseparated by a knife slot 2317 and another electrode 2314 located at thedistal tip 2318. The lateral and distal electrodes 2312, 2314 areseparately and independently controllable. Accordingly, the lateral anddistal electrodes 2312, 2314 can be separately and independentlyenergized. This configuration enables the distal tip 2318 of theflexible circuit electrode 2310 to be used for touching up aroundbleeding areas at the surgical site.

FIG. 102 is a section view of a flexible circuit electrode 2320configured to enable separate and independent control of the outer edges2326 a, 2326 b of the flexible circuit electrode 2320, according to oneaspect of the present disclosure. The flexible circuit electrode 2320comprises a first electrode 2322 that is disposed along a planar surfaceof a jaw of an end effector and a second electrode 2324 that is disposedalong the outer edges 2326 a, 2326 b. A knife slot 2328 is definedbetween the first and second electrodes 2322, 2324. The first and secondelectrodes 2322, 2324 are separately and independently controllable.Accordingly, the first and second electrodes 2322, 2324 can beseparately and independently energized. This configuration enablescontrol of the outside edges of the flexible circuit electrode 2320 tobe used for touching up areas or to allow the user to turn off thesecond electrode 2324 at the outer edges 2326 a, 2326 b when operatingaround delicate structures.

It will be appreciated, that the various flexible circuit electrodeconfigurations shown in FIGS. 100-102 can be incorporated in one aspect.Accordingly, any one of the various aspects of the electrodeconfigurations shown in FIGS. 100-102 can be combined to control variousswitching areas and modes of an end effector. Accordingly, one aspectcomprises a combination of the flexible circuits 2300 and 2310 asdescribed in FIGS. 100 and 101. Another aspect, comprises a combinationof the flexible circuits 2300 and 2320 as described in FIGS. 100 and102. Another aspect, comprises a combination of the flexible circuits2310 and 2320 as described in FIGS. 101 and 102. Finally, another aspectcomprises a combination of the flexible circuits 2300, 2310, and 2320 asdescribed in FIGS. 100-102. Thus, the flexible circuit electrode can beselectively turned on and off in different areas, according to oneaspect of the present disclosure.

C. Techniques for Switching and Controlling Radio Frequency (RF)Flexible Circuit Electrodes

FIGS. 103-113 illustrate techniques for switching and controlling aradio frequency (RF) flexible circuit electrode, according to variousaspects of the present disclosure. FIG. 103 is a diagram illustratingcomponents and interconnections of a system 2400 of an electrosurgicalinstrument for switching and controlling a radio frequency (RF) flexiblecircuit electrode 2406, according to one aspect of the presentdisclosure. The interconnections between the switching and controllingcan be electrically interconnected via a flexible circuit. The system2400 comprises a control circuit 2402 coupled to a generator 2404. Thecontrol circuit 2402 may comprise an application specific integratedcircuit (ASIC), microprocessor, microcontroller, field programmable gatearray (FPGA), programmable logic device (PLD), among other digitaland/or analog circuits. The generator 2404 is coupled to the flexiblecircuit electrode 2406. The control circuit 2402 is configured toreceive one or more inputs 2408 and provide one or more control outputs2410 to control the operation of the electrosurgical instrument. Anoptional expansion interface 2412 may be provided.

Some examples inputs 2408 to the control circuit 2402 include, withoutlimitation, any sensor with analog, I²C, serial communication, ordigital interface. These sensors include, without limitation,thermistors, thermocouples, piezoelectric film temperature, pressure,force load cell for pressure or force measurement, Hall effect orencoder sensors to measure position of clamp arm or closer trigger,switch inputs (dome, tactile, capacitive). When the control circuit 2402comprises an ASIC, microprocessor or FPGA, additional inputs 2408 can beincorporated into the electrosurgical instrument.

Some examples control outputs 2410 from the control circuit 2402include, without limitation, solid or blinking LED's to indicate to thesurgeon state of the instrument (RF energy delivery, high temperature ofclamp arm, and seal complete. Additional outputs 2410 include hapticmotor control to provide tactile feedback to surgeon. Stepper or pulsewidth modulation (PWM) outputs 2410 can be utilized for motor control ofthe knife to advance the knife after seal is complete or in conjunctionwith RF energy as the seal is completed for a particular electrodesegment. Additional outputs 2410 may be employed to turn on relays ortransistors to change the electrode (inside/outside, tip electrode,inner/outer, segment of the electrode). Display outputs 2410 includeliquid crystal display (LCD) outputs to provide visual feedback tosurgeon. When the control circuit 2402 comprises an ASIC, microprocessoror FPGA, additional control outputs 2410 can be incorporated into theelectrosurgical instrument.

The system 2400 provides a means for switching and control of the RFflexible circuit electrode 2406. The circuit configurations of thesystem 2400 can be assembled on a flexible circuit or rigid flexiblecircuit that incorporates the RF flexible circuit electrodes 2406. Thecircuitry of the system 2400 may be located in the handle of theelectrosurgical instrument and can be located on the flexible circuit inany location (i.e., the tail of the flexible circuit or near the RFflexible circuit electrode 2406) that enables the desired functionality.To enable the switching of energy to the RF flexible circuit electrode2406 the user of the electrosurgical instrument can provide an inputthat the RF generator 2404 receives to switch the energy on to the RFoutput pins of the generator 2404 according to various algorithms. Inone aspect, the generator 2404 receives the input on the handswitchwires of the generator 2404. In one aspect, the handswitch input to thegenerator 2404 can be an analog input (based on voltage measured beingwith in defined range for input) or it can be received digitally via acommunication protocol.

FIG. 104 is diagram of the system 2400 for switching and controlling aradio frequency (RF) flexible circuit electrode 2406 shown in FIG. 103where an application specific integrated circuit (ASIC) is employed forthe control circuit 2402, according to one aspect of the presentdisclosure. As shown in FIG. 104, an electrosurgical instrument 2420 isdepicted in block diagram form. The electrosurgical instrument 2420comprises a control circuit 2402 implemented as shown in FIG. 104 as anASIC. The electrosurgical instrument 2420 also comprises a serialcommunication memory 2426, one or more expansion blocks 2428, 2430 eachcoupled to corresponding expansion circuits 2427, 2429. Theelectrosurgical instrument 2420 also comprises an analog-to-digitalconverter 2432 (ADC), a serial communication interface 2438, a bank ofswitches 2436 to indicate various states of the electrosurgicalinstrument 2420. The electrosurgical instrument 2420 also includesvarious LEDs 2436 to indicate states of the electrosurgical instrument2420. The electrosurgical instrument 2420 is coupled to and receivesenergy signals and information from a generator 2404 and can communicateinformation to the generator 2404.

The control circuit 2402 comprises one or more memory blocks 2422, 2424.The first memory block 2422 is coupled to the second memory block 2424,to an input/output (I/O) processor 2444, and a frame processor 2450. Thesecond memory block 2424 is coupled to a position encoder 2448, a motorcontroller 2446, a PWM processor 2442, and an input processor 2440. Aserial data processor 2452 is coupled to first and second expansionblocks 2428, 2430, where each one is coupled to one or more expansioncircuits 2427, 2429. The serial data processor 2452 controls the serialreceiving (RX) and transmission (TX) functions.

The control circuit 2402 receives various inputs and outputs. In oneaspect, for example, the frame processor 2450 of the control circuit2402 is in two-way communication with the generator 2404. The inputprocessor 2440 receives inputs from the switch bank 2436, where theswitches indicate a state of the electrosurgical instrument 2420.Temperature sensors and other sensor inputs are provided to the ADC2432, which is in coupled to the I/O processor 2444. A serialcommunication interface 2434 also is coupled to the I/O processor 2444.Device trigger inputs are coupled to the position encoder 2448. In oneaspect, the input to the position encoder 2448 may be a quadratureencoder input, for example.

The control circuit 2402 also provides various control outputs. Forexample, the stepper motor controller 2446 provides control outputs toone or more motors of the electrosurgical instrument 2420. The PWMprocessor 2442 generates PWM waveforms and outputs the PWM waveforms toone or more motors of the electrosurgical instrument 2420. One or moreoutputs from one of the memory blocks 2424 is coupled to one or moreLEDs 2438 of the electrosurgical instrument 2420. Additionalfunctionality may include, without limitation, discrete inputs, discreteoutputs, serial communication memory, and/or additional serial ports.

With reference now to FIGS. 103 and 104, the use of an ASIC,microprocessor, microcontroller, FPGA, and/or PLD for the controlcircuit 2402 provides the ability of processing input and output controloccur locally (in the electrosurgical instrument 2420) rather thanrequiring the generator 2404 to process the input and output controls.This may provide faster real time control of outputs based on the inputsreceived by the expansion interface box. This expansion interface 2412shown in FIG. 103, would enable the generator 2420 system to provideexpanded capabilities such as high power, monopolar RF capability,combined RF/ultrasonic operation, control, or provide additional powerto outputs such as motors, LCD displays, LED's 2438.

The ASIC implementation of the control circuit 2402 shown in FIG. 104,is configured to provide circuitry within the ASIC control circuit 2402for interfacing and processing inputs and outputs. The ASIC controlcircuit 2402 can accept up to 8 or more discrete inputs and 8 or morediscrete outputs (open drain [pull low] or totem pole type). The controlcircuit 2402 can interface with the generator 2404 utilizing anysuitable communication protocol. The generator 2404 receives the statusof the inputs and sends command to the ASIC control circuit 2402 to turnon outputs. This ASIC control circuit 2402 is placed on the flexiblecircuit or a rigid flexible circuit and is located within the handle ofan electrosurgical instrument 2420 including, without limitation,monopolar and/or bipolar radio RF instruments, microwave instruments,reversible and/or irreversible electroporation instruments, and/orultrasonic instruments, or any combination thereof.

FIG. 105 is an electrical schematic of the system 2400 for switching andcontrolling a radio frequency (RF) flexible circuit electrode shown inFIGS. 103 and 104, according to one aspect of the present disclosure.The system 2400 comprises an ASIC control circuit 2402 and a connection2454 to the system I/O. The electrically conductive interconnections can2456 be formed on a flexible circuit or a rigid flexible circuit coupledto the flexible circuit electrode 2406.

FIG. 106 is a diagram serial communication circuit 2460 that may beemployed by the system 2400 shown in FIGS. 103, 104, according to oneaspect of the present disclosure. The serial communication circuit 2460may be an I²C serial communication interface comprising a multi-master2462, multi-slave 2464 a, 2464 b, 2464 c, single-ended, serial computerbus typically used for attaching lower-speed peripheral integratedcircuits to processors and microcontrollers. The serial communicationcircuit 2460 provides a standard serial port used to communicate to awide variety of commercial off-the-shelf electronic components. Theserial communication circuit 2460 may be employed to communicationto/from multiple components using a single 2-wire serial bus, asdescribed in connection with FIGS. 103 and 104, for example. The serialcommunication circuit 2460 can be used to interact with I²C compatibletemperature sensors, non-volatile memory (e.g., EEPROMs), motorcontrollers, analog-to-digital converters (ADC) and DAC (e.g., fortissue sensing, nerve stimulation, etc.), real time clocks, LCD driversfor displays, and/or position/angle sensors, for example. In one aspect,the I/O processor 2444 shown in FIG. 104 may be implemented using acircuit similar to the serial communication circuit 2460.

FIG. 107 is a waveform generator circuit 2470 configured to generate upto 4 synchronous arbitrary digital waveforms 2474 that may be employedby the system 2400 shown in FIGS. 103 and 104, according to one aspectof the present disclosure. As shown in FIG. 107, the 4 synchronousarbitrary digital waveforms 2474 generated by the waveform generatorcircuit 2470 are output to various external circuit components 2472. Inone aspect, the waveform generator circuit 2470 may be employed as thePWM processor 2442 shown in FIG. 104. The synchronous arbitrary digitalwaveforms 2474 may be employed as custom digital communication protocolto the external components 2472. The synchronous arbitrary digitalwaveforms 2474 also may provide clocks or other required signals to theexternal components 2472 (e.g., to reduce the number of componentsrequired for expanded functionality). The synchronous arbitrary digitalwaveforms 2474 also may be provided to DAC converters (e.g., analogreference voltage, nerve stimulation), blinking LEDs, change tone of asounder, and/or piezo driver, for example.

FIG. 108 is a stepper motor control circuit 2480 configured to drive astepper motor 2482 that may be employed by the system 2400 shown inFIGS. 103 and 104, according to one aspect of the present disclosure.The stepper motor control circuit 2480 provides stepper motor controlfor the stepper motor 2482 and can drive a specified number of steps ina given direction OR drive until an external stop switch is thrown. Thestepper motor control circuit 2480 also can control ramp rates, speed,number of steps, etc., configured by the generator 2404 as shown inFIGS. 103 and 104, for example. In one aspect the motor controller 2446shown in FIG. 104 may be implemented as the stepper motor controlcircuit 2480, for example.

FIG. 109 is a quadrature encoder 2490 for sensing the position of arotating disk 2492 that may be employed by the system 2400 shown inFIGS. 103 and 104, according to one aspect of the present disclosure.FIG. 110 is a schematic diagram of the quadrature encoder 2490 shown inFIG. 109, according to the present disclosure. With reference now toFIGS. 109 and 110, in one aspect the quadrature encoder 2490 comprises adisk 2492 configured to rotate about a shaft 2494. The disk 2492comprises outer slits 2496 and inner slits 2498, where the outer andinner slits 2496, 2498 are alternating and where the outer slits 2496are disposed about an outer diameter of the disk 2492 relative to theinner slits 2498, which are disposed about an inner diameter of the disk2492. A first light emitter 2401 is positioned on one side of the disk2492 to transmit light through the outer slits 2496 to be detected by afirst light detector 2403 located on the other side of the disk 2492. Asecond light emitter 2405 is positioned on one side of the disk 2492 totransmit light through the inner slits 2498 to be detected by a secondlight detector 2407 located on the other side of the disk 2492.

As shown in FIG. 110, as the disk 2492 rotates the light detected at thefirst detector 2403 (A) and the light detected at the second detector2407 (B) produce alternating waveforms 2409, 2411, respectively, thatare in quadrature (i.e., 90° out phase relative to each other). Thesewaveforms 2409, 2411 are provided to a position encoder circuit 2413 todetermine the current position of a mechanism coupled to the shaft 2494of the disk 2492. In one aspect, the position encoder circuit 2413 maybe the position encoder circuit 2448 of the control circuit 2402 shownin FIG. 104 such that the control circuit 2402 can determine the currentposition of a mechanism coupled to the shaft 2494 of the disk 2492. Thecurrent position information can be communicated to the generator 2404(FIG. 104) either automatically or upon request of the generator 2404.In one aspect, for example, the quadrature encoder 2492 may be employedto determine the position of the knife blade, among others.

FIG. 111 is a section view of a flexible circuit electrode 2500comprising a sensing layer 2502 disposed below an electricallyinsulative layer 2504 (e.g., polyimide, polyester, fluorocarbon, or anypolymeric material, or any combinations thereof), which is disposedbelow an electrically conductive layer 2506, according to one aspect ofthe present disclosure. The flexible circuit electrode 2500 alsocomprises a knife slot 2508. With the electronics configurationdescribed in connection with FIGS. 103 and 104, the control logic 2520shown in FIG. 113 can be incorporated into the system 2400 (FIGS. 103,104) of the electrosurgical instrument 2420 (FIG. 104) to measure thetemperature of the end effector clamp. The sensing layer 2502 maycomprise a temperature sensitive device or material such as, forexample, a thermocouple, thermistor, or piezoelectric film that ismounted to the clamp arm between the electrically insulative layer 2504of the flexible circuit and the electrode 2500 on the clamp arm, or anycombination thereof. Once measured by the system 2400, the temperaturecan be displayed on an LCD or LED(s) lit solidly or blinking to indicatethat the temperature is above a threshold where damage to surroundingtissue could result if the clamp arm comes into contact with thistissue. The measured temperature could also be utilized in an algorithmrunning in the generator 2404 (FIGS. 103, 104) to adjust the currentprovided to the RF flexible circuit electrode 2500 to preventundesirable damage to tissue.

FIG. 112 is a plan view of a segmented flexible circuit electrode 2510comprising four segments 2512 a, 2512 b, 2512 c, 2512 d, according toone aspect of the present disclosure. In various aspects, the segmentedflexible electrode 2506 can be segmented into multiple zones. Althoughthe example segmented flexible circuit electrode 2510 shown in FIG. 111comprises four independently controllable segments or zones, a segmentedflexible circuit electrode according to the present disclosure maycomprise at least two segments or zones. One or more of the segments2512 a-2512 d may comprise a separate LED to indicate its activationstatus. Accordingly, the RF energy to one of the segments 2512 a-2512 dmay be switched on or off independently as required by an algorithmbased on the measured temperature. In one aspect, the segmented flexiblecircuit electrode 2506 also may comprise the sensing layer 2502 of theflexible circuit electrode 2500 as described in connection with FIG.111. The first three segments 2512 a-2512 c are separated by a knifeslot 2514 and the fourth segment 2512 d is located at the distal tip2516 of the flexible circuit electrode 2510.

FIG. 113 is a logic diagram 2520 for controlling a segmented flexiblecircuit electrode that may be employed by the system shown in FIGS. 103and 104, according to one aspect of the present disclosure. According toone of the logic diagram 2520, a control circuit 2402, such as thecontrol circuit 2402 described in connection with FIGS. 103 and 104,receives various inputs such as inputs from a temperature sensing layer2502 disposed on a flexible circuit electrode 2500, 2510 as described inconnection with FIGS. 111 and 112. The control circuit 2402 also mayreceive an energy activation/deactivation signal from a switch disposedon the electrosurgical instrument. As shown in FIG. 113, the controlcircuit 2402 receives a signal from the switch to turn on 2522 oractivate the RF energy. The control circuit 2402 provides 2524 a commandto turn on the RF energy and thus electrical current flows to theflexible circuit electrode 2500, 2510 to treat tissue. The controlcircuit 2402 monitors the temperature of the flexible circuit electrode2500, 2510 by monitoring the temperature sensing layer 2502. The controlcircuit 2402 indicates 2526 the measured temperature either by turningon or off selected LEDs or simply displaying the temperature on a LCD.The control circuit 2402 compares 2528 the temperature to apredetermined value and when the temperature exceeds a predeterminedthreshold, the process continues along Yes branch to reduce 2530 thecurrent to the flexible circuit electrode 2500, 2510. At which point,the control circuit 2402 may indicate 2532 the over temperaturecondition by turning an LED on, blinking the LED, changing the color ofthe LED, displaying change or temperature or some other message on theLCD. When the temperature does not exceed the predetermined threshold,the process continues along No branch to maintain 2534 the currentlevel.

D. Flexible Circuit Electrode for Switching and Controlling Data Storage

In various aspects, the flexible circuit electrode for switching andcontrolling data storage may be configured to store use data for rootcause investigation. Utilizing a flex circuit electrode, sensors, and acontroller (ASIC, Microprocessor, or FPGA), additional inputs and outputcontrols may be enabled. Storing this information in the device handle,or generator, would allow users that are performing a root causeinvestigation on a returned device, full access to the detailed inputsand outputs that were utilized with the instrument during the procedure.

E. Multi Layer Flexible Circuit Electrode Including Embedded MechanicalTemperature Switch

FIGS. 114-118 illustrate a mechanical temperature switch embedded in amulti layer flexible circuit electrode to implement flexible circuitswitching electrodes based on the bimetal temperature principle,according to one aspect of the present disclosure. FIG. 114 is a crosssection view of a multilayer flexible circuit electrode 2600 comprisinga mechanical switch in the form of a dome 2602 disposed on the lowestlayer 2604 of the multilayer flexible circuit electrode 2600 in anon-contact state, according to one aspect of the present disclosure.The dome 2602 is configured to expand and contract in response tochanges in temperature. For example, in one aspect the dome 2602 mayexpand in response to an increase in temperature and in another aspect,the dome 2602 may contract in response to a decrease in temperature. Thetemperature control element, such as the dome 2602, is thus incorporatedinto the flexible circuit electrode 2600 for electrosurgical deviceapplications. The dome 2602 mechanical switch is embedded in the layersof the multilayer flexible circuit electrode 2600. In the example shownin FIG. 114, the dome 2602 expands to make contact when a predeterminedtemperature is reached. Using a multilayer flexible circuit electrode2600, a contact dome 2602 is placed on the lowest layer 2604. In a lowtemperature state, the dome 2602 does not make contact with a circuit onan adjacent layer 2606. When the temperature increase, the dome 2602expands and makes electrical contact with a circuit on the adjacentlayer 2606. FIG. 115 is a lower plan view of the multilayer flexiblecircuit electrode 2600 shown in FIG. 114, according to one aspect of thepresent disclosure. FIG. 116 is an upper plan view of the multilayerflexible circuit electrode 2600 shown in FIG. 114, according to oneaspect of the present disclosure.

FIG. 117 is a cross section view of the multilayer flexible circuitelectrode 2600 showing the dome 2602 disposed on the lowest layer 2604of the multilayer flexible circuit electrode 2600 in an electricalcontact state, according to one aspect of the present disclosure. Asshown in FIG. 117, the dome 2602 is in an expanded state and in iselectrical communication with a circuit on an adjacent layer 2606 of themultilayer flexible circuit electrode 2600.

FIG. 118 is a cross section view of a multilayer flexible circuitelectrode 2610 comprising a mechanical switch in the form of a spring2612 disposed on the lowest layer 2614 of the multilayer flexiblecircuit electrode 2610 in a non-contact state, according to one aspectof the present disclosure. The spring 2612 is configured to expand andcontract in response to changes in temperature. For example, in oneaspect the spring 80012 may expand in response to an increase intemperature and in another aspect, the spring 2612 may contract inresponse to a decrease in temperature. The temperature control element,such as the spring 2612, is thus incorporated into the flexible circuitelectrode 2610 for electrosurgical device applications. The dome 2602mechanical switch is embedded in the layers of the multilayer flexiblecircuit electrode 2610. In the example shown in FIG. 118, the spring2612 expands to make contact when a predetermined temperature isreached. Using a multilayer flexible circuit electrode 2610, a contactspring 2612 is placed on the lowest layer 2614. In a low temperaturestate, the spring 2612 does not make contact with a circuit on anadjacent layer 2616. When the temperature increase, the spring 2612expands and makes electrical contact with a circuit on the adjacentlayer 2616.

F. Segmented Flexible Circuit Electrode Including Sensor Configured toProvide Feedback to a Motorized Knife Control Circuit to ControlPosition of Motorized Knife

FIGS. 119-121 illustrate a segmented flexible circuit electrode 2700including a sensor configured to provide feedback to a motorized knifecontrol circuit for controlling the position of the motorized knife2702, according to one aspect of the present disclosure. Positioncontrol of the knife 2702 may be implemented utilizing the controlcircuit 2402 of the electrosurgical instrument 2420 control system 2400described in connection with FIGS. 103 and 104 and the position andmotor controlled circuits described in connection with FIGS. 108-110,for example. The motorized knife 2702 is configured to reciprocatewithin a knife slot 2706.

The segmented flexible circuit electrode 2700 comprises four separateand distinct electrode segments 2704 a, 2704 b, 2704 c, 2704 d that canbe independently energized. Each of the electrode segments 2704 a, 2704b, 2704 c, 2704 d comprises sensor elements 2708 a, 2708 b, 2708 c, 2708d to detect tissue presence and/or tissue seal. The sensor elements 2708a-2708 d may comprise pressure or thermal sensors to detect tissuepresence and tissue seal may be determined by tissue impedance feedbacktechniques. The sensors 2708 a-2708 d may be embedded in or disposed onthe segmented electrode elements 2704 a-2704 d, respectively. Forexample, prior to applying energy to the tissue via one of the segmentedflexible electrode segments 2704 a-2704 d the tissue is rich in moistureand the impedance of the tissue is very low. Applying RF energy to thetissue to effect a seal desiccates the tissue making it less conductiveand thus increases the tissue impedance. Upon completion of the seal,the desiccated tissue will generally have a very high impedance.Impedance may be measured by the control circuit 2402 by measuring thedrive current through the segmented flexible electrode segments 2704a-2704 d and the voltage between the segmented flexible electrodesegments 2704 a-2704 d and a return path.

The control circuit 2402 employs feedback from the sensor elements(pressure, thermal) and the tissue impedance measurements to control theposition of the motor driven knife 2702. In one aspect, for example, thecontrol circuit 2402 will drive the knife 2702 only as far as tissue islocated within the jaw of the end effector. This technique providesknife 2702 travel along the knife slot 2706 permitting simultaneouscutting and sealing of tissue while preventing the knife 2702 fromadvancing distally along the slot 2706 until the pressure or thermalsensor 2708 a-2708 d “detects” the presence of tissue within the jaws ofthe end effector and/or further detecting when a tissue seal is effectedby measuring the tissue impedance.

FIG. 119 illustrates the segmented flexible circuit electrode 2700 whereonly the proximal electrode segment 2704 a is activated, according toone aspect of the present disclosure. The proximal electrode segment2704 a is activated once tissue (not shown for clarity of disclosure) isdetected by the pressure or thermal sensor 2708 a located in theproximal electrode segment 2704 a. Activation of the proximal electrodesegment 2704 a seals the tissue and signals the control circuit 2402(FIG. 104) to advance the motor controlled knife 2702 longitudinally tocoincide with the proximal electrode segment 2704 a by the controlcircuit 2402 (FIG. 104). A pressure sensor 2708 a located in theproximal electrode segment 2704 a detects the presence of tissue. Thecontrol circuit 2402 receives the feedback signal from the sensor andactivates the proximal electrode segment 2704 a. The control circuit2402 advances the knife 2702 along the extent of the proximal electrodesegment 2704 a upon receiving the tissue presence feedback signal fromthe pressure sensor 2708 a. Alternately, the feedback signal to thecontrol circuit 2402 is provided by a thermal sensor 2708 a thatindicates the completion of a tissue seal. Upon receiving the tissueseal feedback signal, the control circuit 2402 advances the knife 2702along the extent of the proximal electrode segment 2704 a where thetissue is located. Once tissue is detected, the proximal electrodesegment 2704 a is energized to seal the tissue and the knife 2702 isadvanced through the slot 2706.

FIG. 120 illustrates a segmented flexible circuit electrode 2700 wherethe intermediate electrode segment 2704 b is activated, according to oneaspect of the present disclosure. The motor controlled knife 2702 is nowextended beyond the extent of the proximal electrode segment 2704 a andextends longitudinally into the intermediate electrode segment 2704 b bythe control circuit 2402 (FIG. 104). As previously discussed,advancement of the knife 2702 into the intermediate electrode segment2704 b is controlled by the control circuit 2402 when tissue is detectedin the intermediate electrode segment 2704 b. Once tissue is detected bythe sensor 2708 b, the intermediate electrode segment 2704 b isenergized to seal the tissue and the knife 2702 is advanced through theslot 2706.

FIG. 121 illustrates a segmented flexible circuit electrode 2700 wherethe distal electrode segment 2704 c is activated, according to oneaspect of the present disclosure. The motor controlled knife 2702 is nowextended beyond the extent of the proximal and intermediate electrodesegments 2704 a, 2704 b and extends longitudinally into the distalelectrode segment 2704 c by the control circuit 2402 (FIG. 104). Aspreviously discussed, advancement of the knife 2702 into the distalelectrode segment 2704 c is controlled by the control circuit 2402 whentissue is detected in the intermediate electrode segment 2704 b. Oncetissue is detected by the sensor 2708 c, the distal electrode segment2704 c is energized to seal the tissue and the knife 2702 is advancedthrough the slot 2706.

It will be appreciated that when tissue spans two or more electrodesegments, the two or more electrode segments will be activated and theknife 2702 will be driven forward by the motor under control of thecontrol circuit 2402 (FIG. 104). Further, the distal electrode elementsegment 2704 d also may comprise a sensor 2708 d and may be energizedindependently whether or not tissue is detected by the sensor 2708 d atthe location of the distal tip.

G. Multi-Zone Segmented Flexible Circuit Electrode Configured to OutputDifferent Algorithms and Treat for Each of the Zones Independently

FIG. 122 illustrates a multi-zone (1, 2, 3) segmented flexible circuitelectrode 2800 configured to output different algorithms for each of thezones 1-3 and treat tissue in each of the zones 1-3 independently,according to one aspect of the present disclosure. The disclosedmulti-zone segmented flexible circuit electrode 2800 comprises threeseparate electrode segments 2802 a, 2802 b, 2802 c that defines threeseparate and independently activatable zones 1-3. A different algorithmcan be outputted to each of the electrode segments 2802 a-2802 c in eachzone 1-3 to treat tissue located in each of the different zones 1-3independently based on tissue type. Since tissue is not homogenous, thedisclosed multi-zone segmented flexible circuit electrode 2800 enablesthe electrode segments 2802 a-2802 c to apply a different algorithm indifferent zones 1-3 to enable at least three different types of tissueto be treated therapeutically differently.

In an effort to achieve an algorithm that is suitable for treating avariety of tissue types, the multi-zone segmented flexible circuitelectrode 2800 technique enables the treatment of tissue located inzones 1, 2, or 3 in a full byte of the jaw assembly differently. Thus adifferent algorithm can be employed to treat each tissue type and outputmultiple algorithms simultaneously for an optimized outcome.Accordingly, the disclosed multi-zone segmented flexible circuitelectrode 2800 enables the selective treatment of tissue within zones1-3 to optimize tissue sealing and reduce thermal damage.

The multi-zone segmented flexible circuit electrode 2800 can be layeredand function independently. Utilizing tissue sensing techniques, eachelectrode segment 2802 a-2802 c can then output a separate algorithmthat is specifically configured for the tissue that is being treated inthat zone. Treating zones 1-3 independently provides optimized tissueeffects and minimize unintended damage. It will be appreciated that themulti-zone segmented flexible circuit electrode 2800 may comprise atleast two electrode segments 2802 a-2802 b and in other aspects maycomprise more than three electrode segments 2802 a-2802 c, withoutdeparting from the scope of the present disclosure.

H. Technique for Implementing a Multiplexer with Flexible ElectronicCircuits to Provide Improved Control Methods

FIGS. 123-124 illustrate a technique for implementing a multiplexer 2900with flexible electronic circuits to provide improved control methods,according to one aspect of the present disclosure.

FIG. 123 illustrates a two line multiplexer 2900 (MUX) implemented withflexible electronic circuits, according to one aspect of the presentdisclosure. A multiplexer is a device that selects one of several analogor digital input signals and forwards the selected input into a singleoutput line. Generally, a multiplexer may comprise n select lines toselect 2^(n) input lines to send to a single output line. For themultiplexer 2900 (MUX), n=2, thus two input select lines S0, S1 are usedto multiplexed inputs provides 2²=4 select lines (1-4) that areforwarded to a single output line (Output). A multiplexer can increasethe functionality of an electrosurgical instrument over a fixed hardwareenvironment. Accordingly, in one aspect, the multiplexer 2900 may beemployed to switch algorithm control between RF and ultrasonic energy inan electrosurgical instrument.

In one aspect the control circuit 2402 (FIG. 104) of the generator 2404(FIG. 104) has eight inputs/outputs. If one input is dedicated to asingle activation button, seven inputs remain available to a multiplexerto provide 2⁷=128 different combinations of lines that can be selectedto forward to a single output line. This multiplexer configuration cansimplify the use of transistors or relays to act as switches on powerlines, to enable/disable undesired lines. The multiplexer, however, canbe used for more than just the power lines and can be used for signallines as well.

FIG. 124 illustrates a jaw configuration 2910 with independentlyactuatable electrodes 2912 a-2912 h, according to one aspect of thepresent disclosure. A knife slot 2914 is provided between banks ofindependently actuatable electrodes 2912 a-2912 h and a distal tipelectrode 2916, which also can be independently actuated. A flexibleelectronic circuit based multiplexer can be employed to select multipleoutputs to the segmented electrodes 2912 a-2912 h. This techniqueprovides additional output control for turning on and off additionalfeatures of the electrosurgical instrument by making use of flexiblecircuit electrode electronics, specifically sensors, transducers andmore.

Referring now to FIGS. 123-124, in various aspects, a 128-to-1 amultiplexer can select one of 128 combinations of lines for switching onand off based on eight input select lines. The multiplexer configurationcan enable multiple combinations of the segmented electrodes 2912 a-2912h to sense tissue presence, provide profile of impedance in tissue,better characterize tissue, determine orientation in the jaw, provide“smarter” switching between ultrasonic and RF, apply heat only in lowimpedance sections of tissue instead of across entire load in jaws toimprove speed or reduce charring/inadvertent burning, better allow spotcoagulation and scoring and use the multiplexer for auto-detection andprovide a separate switch that the user presses, energize segmentedelectrodes. Additionally, the multiplexer configuration can turn sensorsor transducers on/off, enable or disable a multi-transducer model, applypower to and read force sensors, pressure sensors, and temperaturesensors, determine upperology of tissue. The multiplexer configurationalso can turn lights or LEDs on/off and make better use of buttons,among other features.

In some aspects, employing a multiplexer in combinations with thesegmented electrode 2910 provides multiple combinations of electrodes tolimit the number of power transistors or isolation relays by putting asingle transistor or relay on each output of the multiplexer which canbe located by the control circuit 2402 (FIG. 104). The output of thetransistors or relays can be on the hand switch circuit, which can thenallow for the portion of the flexible circuit to go down the shaft ofthe instrument. In other aspects, a multiplexer may enable the user toimitate monopolar RF operation when the tip electrode 2916 onlyactivated or when the sides of the segmented electrode 2910 areelectrified. In yet other aspects, a multiplexer may be providedadvanced bipolar RF energy such that the generator 2404 (FIG. 104) canswitch through electrode pairs to allow the generator 2404 to identifywhere the tissue is located in the jaws. Also, the generator 2404 canidentify impedances to know when all of the tissue or only a portion ofthe tissue requires additional energy or more time effect a seal. Thistechnique can be employed to activate only on sections of tissue thatneed to be activated upon or when a short circuit is present, thegenerator 2404 can switch to ultrasonic energy drive. Additionally,there are other ultrasonic techniques to determine the occurrence of atrue short circuit versus the presence of low impedance tissue(frequency changes on metal, in addition to auditory change frommetal-on-metal contact). Finally, in one aspect, when the tissueimpedance is greater than the termination impedance but less than anopen circuit impedance across all electrode combinations, ultrasonicenergy may be delivered by the generator 2404 to effect the seal ratherthan bipolar RF energy.

I. Flexible Circuit Segmented Electrode Including Inner and OuterMaterials Having Different Thermal Conductivity Properties for AlteringTissue Effects

FIG. 125 illustrates a flexible circuit segmented electrode 3000comprising an inner material 3002 and an outer material 3004 that havedifferent thermal conductivity properties for altering tissue effects,according to one aspect of the present disclosure. The inner and outermaterials 3002, 3004 are disposed on an electrically insulative film3006 (e.g., polyimide, polyester, fluorocarbon, or any polymericmaterial, or any combinations thereof). The flexible circuit segmentedelectrode 3000 may be mass produced for electrosurgical instruments. Theinner and outer materials 3002, 3004 are bonded to the electricallyinsulative film 3006 backing to produce a sub-assembly. The inner andouter materials 3002, 3004 can be produced by laminating metallic sheetsto the electrically insulative film 3006. The shape of the electrode canbe formed by screen printing a protective barrier to the metallic film.This protective barrier permits the shape of the inner and outermaterials 3002, 3004 to be formed by photoetching away the remainingmaterial which does not make up the final shape of the inner and outermaterials 3002, 3004. Finally the flexible circuit segmented electrode3000 is die-cut out leaving an electrode sub-assembly that can be bondedto the jaws of the end effector. The electrically insulative film 3006can have an adhesive or a braze-able surface on the back side of theelectrically insulative film 3006 thus allowing for means of attachmentto the lower or upper jaw elements depending on the device jawconstruction.

Separation of the electrode 3000 with different materials 3002, 3004permits different impedance and power levels to be controlled. The innerand outer materials 3002, 3004 may be selected to have different heatingcharacteristics such that either the inner material 3002 or the outermaterial 3004 faster than the other. For example, the thermal affectedzone may be reduced by selecting an inner material 3002 that heatsfaster than an outer material 3004.

XV. Pressure Sensing A. Flexible Circuit Electrode Including IntegratedPressure Sensor

FIGS. 126-130 illustrates an integrated thin flexible circuit electrode3100 comprising a pressure sensor 3102 integrated with the flexiblecircuit electrode 3100, according to one aspect of the presentdisclosure. FIG. 126 illustrates a thin and flexible circuit electrode3100 comprising a switching pressure sensor 3102, according to oneaspect of the present disclosure. A pressure sensor 3102 (such as a thinflexible sensor known under the tradename TEKSCAN) is attached (e.g.,laminated) to the one side of an electrically insulative layer 3104(e.g., polyimide, polyester, fluorocarbon, or any polymeric material, orany combinations thereof) of the flex circuit electrode 3100. The otherside of the electrically insulative layer 3104 comprises electricallyconductive traces 3106 made of copper, silver, gold, and similarconductive element s or alloys. A knife slot 3108 is provided such thatthe knife can reciprocate therein. The thin and flexible circuitelectrode 3100 comprising a switching pressure sensor 3102 can enable aclosed loop system in the device where the control circuit 2402 (FIG.104) reads the pressure in the jaw elements of the end effector toadjust the duty cycle and/or current of the drive energy. When thepressure is low, the control circuit 2402 can apply more power withoutany additional programming required in the generator 2404 (FIG. 104).

FIG. 127 is a lower plan view of the flexible circuit electrode 3100shown in FIG. 126 showing the pressure sensor 3102, according to oneaspect of the present disclosure. FIG. 128 is a side view of theflexible circuit electrode 3100 shown in FIG. 126 with an embeddedpressure sensor, according to one aspect of the present disclosure. FIG.129 is a plan view of the flexible circuit electrode 3100 shown in FIG.126 with a tissue bundle 3110 present thereon, according to one aspectof the present disclosure. FIG. 130 is a plan view of the flexiblecircuit electrode 3100 shown in FIG. 126 with a vessel present 3112,according to one aspect of the present disclosure.

With reference now to FIGS. 126-130, the thin flexible pressure sensor3102 can be integrated with a flexible circuit electrode 3100 to drive agenerator based on load feedback. For example, an RF generator feedbackcan be customized based on a pressure profile/compression in the endeffector jaws. In one aspect, the thin flexible pressure sensor 3102 maybe in the form of a tape (such as the type provided by TEKSCAN) isintegrated with a flexible layered circuit electrode 3100 to enabledetection of a pressure profile in jaw/compression force and drive theRF generator in response thereto based on the tissue type. For example,when a large bundle of tissue is detected, the RF generator is driven atgreater power and when a small vessel is detected in the center of thejaws, the RF generator is driven according to a sealing algorithm.

B. Flexible Circuit Electrode Including Integrated Pressure Sensor toLocalize or Adjust Closure Pressure

The integrated thin flexible circuit electrode 3100 comprising apressure sensor 3102 described in connection with FIGS. 126-130, may beemployed to localize or adjust closure pressure by controlling the forceon the tissue and pressure regulation using the pressure sensor 3102feedback to the control circuit 2402 (FIG. 104). In other aspects, aflexible circuit electrode may incorporate single, or multiple separatelayers that include small bimetallic discs, interfaced with a currentdelivering wire. As current is applied to the disc, it heats up, and thebimetallic layer causes it to expand. As it expands, the jaw orelectrode would deliver more compression in that area of the jaw.Additionally, utilizing multiple layers, or selectively isolatedsections of a single layer provides a selectably controlled closureforce at unique points of the jaws. This system could be used inconjunction with other systems to generate many different desiredoutcomes. Some possible implementations are described below:

In one aspect, a dynamic pulse closure pressure technique may beemployed. An initial very heavy closure force on activation to ensuremechanical movement of musculature layer is provided before easing offto slow transection to generate optimum hemostasis.

In another aspect, a layer of different compression profiles indifferent sections of jaw may be enabled to selectively engage tissue.One example is to create high tip compression when not activating thedevice to generate good grasping, and then reduce it during energyactivation to ensure uniform treatment.

In yet another aspect, on either the same of different layer, a wiremesh may be arranged to simulate a strain gauge in series with thebimetallic disc system. As a section receives additional pressure fromtissue resistance or other closure load, it will deform the straingauge, increasing its resistance. This results in less current for thediscs, reducing the force that they will produce. This feature willcollectively allow the device to automatically balance the closurepressure uniformly along jaws.

In another aspect, a layer of different discs in patterns radiatingoutward from blade or cut location are provided. Pressure is initiallypulsed, to start inward and then moves outwardly to facilitate fluidtransfer outward away from the upcoming cut, thus allowing theelectrosurgical instrument to apply energy directly to tissue withoutexcess fluid at or near the cut line.

C. Flexible Circuit Electrode Including Selective Electrode Zones (1-3)Activation Employing Piezoelectric Pressure Detection

FIGS. 131-133 illustrate a flexible circuit electrode 3200 comprisingselective electrode zones (1-3) activation employing piezoelectricpressure detection, according to tone aspect of the present disclosure.FIG. 131 illustrates a segmented flexible circuit electrode 3200 dividedinto three activation segments 3202 a, 3202 b, 3202 c, and a knife slot3216, according to one aspect of the present disclosure. FIG. 132 is asection view of the segmented flexible circuit electrode 3200 shown inFIG. 131 showing an layer electrode 3204, a circuit layer 3206, apiezoelectric ceramic sensor layer 3214, according to one aspect of thepresent disclosure. FIG. 133 schematically illustrates a load pressure3210 from tissue being applied to the electrode segments 3202 a, 3202 b(sections 2-3) and a reaction pressure 3211 applied to underlyingceramic piezoelectric sensors 3208 b, 3208 c, according to one aspect ofthe present disclosure.

With reference to FIGS. 131-133, in one aspect, the piezoelectricceramic sensor layer 3214 comprises piezoelectric ceramic sensors 3208a, 3208 b, 3208 c are located in corresponding segmented electrodes 3202a, 3202 b, 3202 c in sections 1-3 of the electrode 3200. Thepiezoelectric ceramic sensor layer 3214 is located below each definedelectrode segments 3202 a-3202 c or zones (1-3). As pressure is appliedto the electrode 3200, the underlying ceramic piezoelectric sensors 3208a-3208 c detect the pressure applied in the sections 1-3. The electrodesegments 3202 a-3202 c of the electrode 3200 are then activated orenabled. For example, as tissue contacts sections 2 and 3 of the distaltip 3212 of the electrode 3200, the electrode segments 3202 b and 3202 cin sections 2 and 3 are enabled while the electrode 3202 a in section 1remains inactive.

The two electrode segments 3202 b, 3202 c are activated when a voltagedifference ΔV, produced by the tissue load pressure 3210 is applied tothe two electrode segments 3202 b, 3202 c and a reaction pressure 3211is applied to the two piezoelectric ceramic sensor 3208 b, 3208 c and tosections 2-3. The voltage difference ΔV developed is response to theapplied pressure 3210, 3211 is detected by the control circuit 2402(FIG. 104). In one aspect, the flexible circuit electrode 3200 isconfigured such that the electrode segments 3202 a-3202 c can beselectively enabled only where tissue is located thereon. This techniqueminimizes heat generation in non-tissue containing sections. In variousaspects, additional sections can be utilized as needed.

In one aspect, the flexible circuit electrode 3200 is coupled to thecontrol circuit 2402 (FIG. 104) that selectively activates sections 1-3of energy delivery by activating the electrode segments 3202 a-3202 cbased on pressure sensed by the piezoelectric ceramic sensor 3208 a-3208c. The flexible circuit electrode 3200 incorporates the piezoelectricceramic sensor 3208 a-3208 c to detect pressure in a finite number ofsections (1-3). Pressure applied to this piezoelectric ceramic layer3214 indicates the presence of tissue in the jaws in that specificsection due to the delta voltage created by the applied pressure. Thissection is then allowed to be active. Sections where no tissue ispresent remain inactive and heat generation is minimized.

XVI. Temperature Sensing A. Flexible Circuit Electrode IncludingEmbedded Optical Temperature Sensor

FIGS. 134-136 illustrate an optical temperature sensor 3300 embedded ina flexible circuit electrode 3302 according to one aspect of the presentdisclosure. FIG. 134 is a plan view of an optical temperature sensor3300 embedded in the flexible circuit electrode 3302, according to oneaspect of the present disclosure. FIG. 135 is as section view of theoptical temperature sensor 3300 embedded in a flexible circuit electrode3302 taken along section line 135-135 as shown in FIG. 134, according toone aspect of the present disclosure. The optical temperature sensor3300 comprises a flexible circuit electrode 3302 with a light pipe 3304embedded therein. The embedded optical temperature sensor 3300 can beincorporated in the flexible electrode 3302 by printing a light pipe3304 of a high index transparent material on a substrate 3310 with alower index of refraction. A photodiode 3306 and an LED 3308 lightsource are fixed and optically coupled at each end of the light pipe3304. Measuring the amount of transmitted light can be used to measuretemperature. The flexible circuit electrode 3302 also defines a knifeslot 3314 to enable a knife to reciprocate therealong.

As shown in FIG. 135, the light pipe 3304 is disposed on a substrate3310 and is covered by a compliant material 3312. The opticaltemperature sensor 3300 can be embedded in the flexible electrode 3302by printing a light pipe 3304 of a transparent material with arefraction index higher than the index of the substrate 3310. The lightpipe 3304 is covered with the compliant material 3312 having a lowerrefraction index than that of the light pipe 3304. This way theequivalent of an optical fiber is achieved. The light transmitted by thelight pipe 3304 depends on the refraction indices of the substrate andcompliant materials involved. The refraction indices depend ontemperature, thus allowing temperature measurement.

In one aspect, the optical temperature sensor 3300 works on theprinciple of variation of transmitted light through an optical fiber,e.g., the light pipe 3304, due to changes of the index of refractionwith temperature. The embedded optical temperature sensor 3300 enablesmonitoring the temperature of the flexible circuit electrode 3302 duringtissue sealing operations. During sealing, the flexible circuitelectrode 3302 may overheat, causing damage to adjacent tissue. Feedbackof electrode temperature to the control circuit 2402 (FIG. 104) can beused to adjust the RF power applied to the flexible circuit electrode3302. This also permits minimizing damage to neighboring tissue.

FIG. 136 is a schematic of a bent fiber section 3320 curved with aradius of curvature R, according to one aspect of the presentdisclosure. FIG. 136 shows a schematic of a curved multimode step indexoptical fiber [19]. The radius of curvature is R and the core diameteris 2ρ_(Core). The refractive indices of the core and cladding aren_(Core), and n_(Cladding), respectively. Optical power is launched atthe beginning of the rectilinear region of the fiber. The geometricaldescription of the core rays in a step-index optical fiber is morecomplex than in a planar waveguide [20], due to the presence of the skewrays. The guidance of the core rays is achieved by ensuring that thepropagation angle, α, satisfies the condition: 0≦α≦α_(c), where thecritical angle (α_(c)) is given by: α_(c)=sin⁻¹(n_(Cladding)/n_(Core)).The expression of the numerical aperture (NA) for the rectilinear regionis given by:

NA=n _(Core)·sin α≦(n _(Core) ² −n _(Cladding) ²)^(1/2)  (1)

However, in the bend optical fiber, the guidance of the core rays canfollow two ways. Only the rays entering the bent part of the fiber inthe meridional plane remain with the same angle of incidence along agiven ray path. On the other hand, the skew rays entering this planeafter the successive reflections within the core, do not follow a simplerepeatable pattern because of the asymmetry introduced by bending thefiber. So when the optical fiber is bent, the local numerical aperturechanges at a given location of the bent optical fiber. The dependence ofthe numerical aperture with the bend is given by [19]:

$\begin{matrix}{{{NA}\left( {R,\rho,\varphi} \right)} = {n_{Core}\left\lbrack {1 - {\frac{n_{Cladding}^{2}}{n_{Core}^{2}}\left( \frac{R + \rho_{Core}}{R - {{\rho \cdot \cos}\mspace{11mu} \varphi}} \right)^{2}}} \right\rbrack}^{1/2}} & (2)\end{matrix}$

where φ is the ray angle at the beginning of the bend, which varies from0° to 180°, ρ_(Core) is the fiber core radius and p is the radialposition in the core satisfying the relation 0≦ρ≦ρ_(Core).

The optical fiber sensor proposed in this paper is based on a macro-bendPOF. In this intensity sensor, the losses induced by the bending effectdepend on the numerical aperture, that change with temperature. Therefractive index of the core and cladding POF depend on the temperature.The POF used in the experiments is a Rayon® Eska® SH-4001 (Mitsubishi,Tokyo, Japan) with core and cladding manufactured using polymethylmethacrylate (PMMA) and fluorinated polymer, respectively. Thetemperature dependence of the core refractive index can be expressed as[21]:

n _(Core)(T)=K ₂ ·T ² +K ₁ ·T+n ₀  (3)

where K₁=−1.15.10⁻⁴(° C.)⁻¹ is the thermo-optic (TO) co efficient of thecore, K₂=−5.173.10⁻⁷(° C.)⁻² is the second order temperature dependenceterm of the core and n₀=1.49538 is the core refractive index at 0° C. Onthe other hand, the temperature dependence of the cladding refractiveindex is given by [22.]:

n _(Cladding)(T)=n _(Cladding)(T ₀)+K ₃·(T−T ₀)  (4)

where K₃=−3.5·10⁻⁴(° C.)⁻¹ is the TO coefficient of the cladding andn_(Cladding)(T₀)=1.403 is the cladding refractive index at the referencetemperature (T₀=+25° C.)

It can be seen that |K₃|>|K₁|. Finally, from Equation (2), the localnumerical aperture in the bent section of the fiber versus thetemperature can be expressed as:

$\begin{matrix}{{{NA}\left( {T,R,\rho,\varphi} \right)} = {{n_{Core}(T)}\left\lbrack {1 - {\frac{n_{Cladding}^{2}(T)}{n_{Core}^{2}(T)}\left( \frac{R + \rho_{Core}}{R - {{\rho \cdot \cos}\mspace{11mu} \varphi}} \right)^{2}}} \right\rbrack}^{1/2}} & (5)\end{matrix}$

A detailed explanation of a similar sensor is given in the attachedarticle. A Temperature Sensor Based on a Polymer Optical FiberMacro-Bend, Alberto Tapetado Moraleda, Carmen Vázquez García, JosebaZubia Zaballa and Jon Arrue, Sensors 2013, 13, 13076-13089;doi:10.3390/s131013076; ISSN1424-8220.

B. Flexible Circuit Bladder Sensor for Sensing Pressure and Temperature

FIGS. 137-138A illustrate a flexible circuit bladder sensor 3400 forsensing pressure and temperature, according to one aspect of the presentdisclosure. FIG. 137 is an exploded view of the flexible circuit bladdersensor 3400, according to one aspect of the present disclosure. FIG. 138is an elevation view of the flexible circuit bladder sensor 3400attached to a jaw member 3410 of an end effector, according to oneaspect of the present disclosure. The flexible circuit bladder sensor3400 is configured to measure force during closure and measuretemperature during treatment using a bladder element 3402 adhered to theback side 3404 of a flexible circuit electrode 3406. The back side 3404of the electrode 3406 comprises a plastic flexible layer usually made ofan electrically insulative material (e.g., polyimide, polyester,fluorocarbon, or any polymeric material, or any combinations thereof).The other side of the electrode 3406 is the tissue contacting side 3408.As shown in FIG. 138, the flexible bladder element 3402 is locatedsomewhere on the tissue contacting portion of the flexible circuit inorder to sense pressure changes when tissue is contacted, clamped, andtreated. In one aspect, the actual pressure sensing element (e.g.,pressure sensing element 3434, see FIG. 138A) can be co-located on theflexible circuit. In other aspects, however, the pressure sensingelement can be located somewhere else in the device.

The flexible circuit bladder sensor 3400 can be configured to measureforce during closure and temperature during treatment employing aflexible micro bladder element 3402 adhered to the back side 3404 of aflexible circuit electrode 3406. Thus, both force and temperature can bemeasured on the flexible circuit electrode 3406 in an electrosurgicaldevice, as referenced herein.

In one aspect, the flexible bladder element 3402 may be fabricated byadhering a flexible sheet to the back of side 3404 of a flexible circuitelectrode 3406 to create a flexible bladder element 3402 of any desiredshape, size, or location on the electrode 3406 area of the flexiblecircuit 3406. In one aspect a tube 3412 is formed between the flexiblesheet and the back side of the flexible circuit electrode 3406. The tube3412 and the bladder element 3402 are in fluid communication and definea volume. The bladder element 3402 and the tube 3412 may be formed as asingle piece unit. In another aspect, the tube 3412 may be formed usingtwo flexible sheets.

The flexible bladder element 3402 is in fluid communication with thetube 3412, which is configured to transmit the pressure in the bladderelement 3402 to a pressure sensing element of a circuit 3420 via an openend 3414 of the tube 3412. The open end 3414 is sealed to the input port3422 of the pressure sensing integrated circuit 3420. Thus, the pressureis contained within a closed system. The tube 3412 extends to a pointwhere the pressure sensing integrated circuit 3420 is located. In oneaspect, a pressure sensing integrated circuit 3420 is attached to theflexible circuit electrode 3406 and converts the pressure to anelectrical signal. In one aspect, the pressure sensing integratedcircuit 3420 may be mounted on the surface of the flexible circuitelectrode 3406.

In operation, when the jaws of the end effector are closed, the bladder3402 compresses and increases pressure in the tube 3412 created by theflexible sheet against the back side 3404 of the flexible circuitelectrode 3406. When the temperature increases, the pressure increasesin the bladder and therefore senses pressure at jaw closure andtemperature during treatment. The circuit is in communication with thecontrol circuit 2402 (FIG. 104).

FIG. 138A is a section view of the pressure sensing integrated circuit3420, according to one aspect of the present disclosure. The pressuresensing integrated circuit 3420 comprises an input port P1 to receivethe input pressure from the tube 3412 and a second port P2, which isnormally open to atmospheric pressure, but can be closed to a vacuum tomeasure absolute pressure applied to the input port P1. The pressuresensing integrated circuit 3420 comprises fluorosilicone gel die coat3424 disposed over an integrated circuit die 3426. A stainless steel cap3428 and a thermoplastic case 3430 enclose the die 3426 and pressurechamber. The die 3426 is bonded 3432 to the thermoplastic case 3430. Thedie 3426 comprises a differential pressure sensing element 3434. Aspressure is applied to port P1, the differential pressure sensingelement 3434 deforms and generates a voltage proportional to the appliedpressure. The voltage is coupled to an external lead frame 3436 by wayof wire bonds 3438. In one aspect, the pressure sensing integratedcircuit 3420 may be a MPXV6115V series sensor integrates on-chip,bipolar op-amp circuitry and thin film resistor networks to provide ahigh output signal and temperature compensation. The pressure sensingintegrated circuit 3420 has a small form factor and benefits from thehigh reliability of on-chip integration. The differential pressuresensing element 3434 comprises a monolithic, signal conditioned, siliconpressure sensor. The sensor combines advanced micromachining techniques,thin film metallization, and bipolar semiconductor processing to providean accurate, high level analog output signal that is proportional toapplied pressure.

C. Flexible Circuit Thermocouple Sensor

FIGS. 139-140 illustrate a flexible circuit thermocouple sensor 3500,according to one aspect of the present disclosure. FIG. 139 is aschematic diagram of the flexible circuit thermocouple sensor 3500,according to one aspect of the present disclosure. FIG. 140 is a sectionview of the flexible circuit thermocouple sensor 3500, according to oneaspect of the present disclosure. With reference now to FIGS. 139 and140, a thermocouple 3502 is provided in a flexible circuit electrode3504 by creating a contact between two dissimilar metals 3506, 3508. Toreduce electromagnetic interference (EMI), the thermocouple 3502 layeris sandwiched. The flexible circuit thermocouple sensor 3500 can beemployed to monitor the temperature of the flexible circuit electrode3504 during sealing.

The thermocouple 3502 can be built in a flexible circuit. If theflexible circuit also contains an RF electrode, special precautionsshould be taken to avoid EMI noise in the thermocouple circuit. Sincethe flexible circuit electrode 3504 may overheat during sealing andcause damage to neighboring tissue, feedback from the flexible circuitelectrode 3504 can be used to adjust the power applied by the generator2404 (FIG. 104). Thus the flexible circuit thermocouple sensor 3500 canbe used to minimize damage to neighboring tissue during sealing.

As shown schematically in FIG. 139, the flexible circuit thermocouplesensor 3500 comprises a thermocouple 3502 formed by creating a contactbetween two dissimilar metals 3506, 3508. The dissimilar metals 3506,3508 are coupled to an instrumentation amplifier 3510, which amplifiesthe low level signal produced by the thermocouple 3502. A guard 3514surrounds the thermocouple metals 3506, 3508 and is driven by the output3516 of a buffer amplifier 3518 to shield the low level signal producedof the thermocouple 3502.

The low level signal produced by the thermocouple 3502 can be masked byEMI when the RF power is applied. EMI noise may be coupled in severalways: (1) Common Mode Noise Coupled by Ground Loop; (2) CapacitiveCoupling; and (3) Magnetic Coupling. For the first two modes, insulatingthe thermocouple and shielding it with the driven guard 3514 is a commonmethod. Having the guard 3514 surrounding the thermocouple 3502connected to a low impedance buffer amplifier 3518 that keeps it at afixed voltage (e.g., ground) makes it very effective in preventing noisecoupling by stray capacitance and leak resistance in the thermocouple3502. The simplified schematic illustrates the canceling of inducedcurrents 3520 due to EMI. Avoiding a large area loop in the thermocouplecircuit is the most effective method to prevent induced noise currents.In a flat geometry, like the flexible circuit, this can be achieved bybalanced canceling loops.

FIG. 140 is a section view of the flexible circuit thermocouple sensor3500, according to one aspect of the present disclosure. The flexiblecircuit thermocouple sensor 3500 comprises an electrically insulativematerial 3522 (e.g., polyimide, polyester, fluorocarbon, or anypolymeric material, or any combinations thereof). The first metal 3506of the thermocouple 3502 is embedded in the electrically insulativematerial 3522 and is coupled to the second metals 3508, which also areembedded in the electrically insulative material 3522. The thermocouple3502 metals 3506, 3508 are surrounded by the guard 3514 conductors,which may be copper, for example.

XVII. Optical Tissue Sensing A. Flexible Circuit Electrode IncludingIntegrated Pulse-Oximeter Sensor

FIGS. 141-142 illustrate a pulse-oximeter sensor integrated in aflexible circuit electrode for identifying blood flow in tissue locatedbetween jaw members of an end effector prior to clamping and cutting,according to one aspect of the present disclosure. The pulse-oximetersensor and/or i-watch technology, LED light sources, and photodiodeoptical sensors positioned within a flexible circuit electrode may beemployed to notify the end user of blood flow within tissue locatedbetween the jaw members of an end-effector.

FIG. 141 illustrates a system 3600 comprising an electrosurgicalinstrument 3602 coupled to a generator 3604, according to one aspect ofthe present disclosure. The electrosurgical instrument 3602 comprises anLED light 3620 located on the handle 3622. The electrosurgicalinstrument 3602 also comprises an end effector 3606 comprising apulse-oximeter sensor 3608 integrated in flexible circuit electrodes3610 a, 3610 b comprising an element 3610 a located in the upper jawmember 3614 a and another element 3610 b located in the lower jaw member3614 b. In another aspect, a wearable device sensor may be integrated inthe flexible circuit electrodes 3610 a, 3610 b. In one aspect, thewearable device sensor comprises i-watch technology, for example.

FIG. 142 is a detail view of the end effector 3606 shown in FIG. 141comprising a pulse-oximeter sensor 3608 integrated in the flexiblecircuit electrodes 3610 a, 3610 b, according to one aspect of thepresent disclosure. The pulse-oximeter sensor 3608 comprises LED lightsources 3616 attached to the flexible circuit electrode 3610 a locatedin the upper jaw member 3614 a and a photodiode optical sensor 3618 isattached to the flexible circuit electrode 3610 b located in the lowerjaw member 3614 b. The LED light sources 3616 and the photodiode opticalsensor 3618 are coupled to the control circuit 2402 (FIG. 104) and/orthe generator 3604 (e.g., the generator 2404 shown in FIG. 104).Similarly, the electrodes 3610 a, 3610 b may be coupled to the controlcircuit 2402 and/or to the generator 3604. The control circuit 2402drives the LED light sources 3616 and the light 3626 is received by thephotodiode optical sensor 3618. The output voltage produced by thephotodiode optical sensor 3618 is indicative of the blood flow 3624and/or oxygen (O₂) levels in the vessel 3612. The control circuit 2402and/or the generator 3604 can be used to determine the blood flow and/oroxygen (O₂) 3624 levels in the vessel 3612 based on the amount of light3626 transmitted by the LED lights sources 3616 is received by thephotodiode optical sensor 3618, where the difference is absorbed byblood flow 3624 in the vessel 3612. Blood can be optically monitoredbased on the absorption of 350-600 nm light by hemoglobin in the blood.

FIG. 141 shows a blood vessel 3612 located between the jaw members 3614a, 3614 b of the end effector 3606. The pulse-oximeter sensor 3608 canbe configured to identify vessels 3612 that may or may not have beenidentified in a tissue bite with a monopolar or bipolar electrosurgicalinstrument 3602. The pulse-oximeter (or i-watch) sensor 3608 enables theidentification of blood flow 3624 within tissue 3612 located between thejaw members 3614 a, 3614 b prior to cutting the tissue 3612.

A surgeon cannot identify the type of tissue 3612 located between thejaw members 3614 a, 3614 b with certainty. The pulse-oximeter sensor3608 comprising LED light sources 3616 and photodiode optical sensors3618, as well as flexible circuit technology can be employed to detectblood flow and/or O₂ 3624 levels in the tissue 3612. Thus, the surgeonwould know when a blood vessel is located in the jaw members 3614 a,3614 b of the electrosurgical instrument 3602. This technique may beemployed to identify the tissue type and determine when blood is presentin a vessel within the tissue 3612 located between the jaw members 3614a, 3614 b. Knowledge of this information may be helpful to surgeons thatlike to march quickly through the tissue 3612.

In operation, the LED light sources 3616 located on one flexible circuitelectrode sends light 3626 through the tissue 3612 and is received bythe photodiode optical sensors 3618. Blood flow and/or O₂ 3624 isrecognized (e.g., similar to a pulse oximeter or i-watch). Theinformation is sent to the generator 3604. The generator 3604 sends amessage to the LED light 3620 on the handle 3622 of the electrosurgicalinstrument 3602, which illuminates when appropriate. The pulse-oximeter3618 and/or i-watch could also be configured to communicate with smartphones or wearables such as the i-watch, fit-bit, among otherapplications to signal information.

B. Flexible Circuit Electrode Including Integrated Electro OpticalSensors for Sensing Tissue Properties

FIGS. 143-147 illustrate electro optical sensors 3700 for sensing tissueproperties integrated with a flexible circuit electrode 3702, accordingto one aspect of the present disclosure. Turning to FIG. 143, whichillustrates an exploded view of an electro optical sensor 3700 forsensing of tissue properties integrated with a flexible circuitelectrode 3702, according to one aspect of the present disclosure. Theelectro optical sensor 3700 is integrated in a flexible circuitelectrode 3702 and comprises a multilayer coating 3704 positioned overan optically transparent window 3706, which is positioned above adiffraction grating 3708. A lens 3710 is positioned between thediffraction grating 3708 and a photo diode 3712. The photo diode 3712 iselectrically coupled to control circuits by way of conductive traces3714 formed on the flexible circuit electrode 3702. A flexible opaqueelectrically insulative layer 3716 is disposed over the optical assemblycomprising the window 3706, the diffraction grating 3708, the lens 3710,and the photo diode 3712. In one aspect, the flexible opaqueelectrically insulative layer 3716 may be made of a polyimide film, suchas Kapton, or polyester, fluorocarbon, or any polymeric material, or anycombinations thereof.

FIG. 144 is a plan view of the flexible circuit electrode 3702comprising an electro optical sensor 3700 for sensing of tissueproperties shown in FIG. 143 integrated in a via 3718 of the flexiblecircuit electrode 3702, according to one aspect of the presentdisclosure. The flexible circuit electrode 3702 comprises a plurality oftraces 3720 and a plurality of vias 3718 to electrically interconnectdifferent layers of the flexible circuit electrode 3702. As with otheraspects of flexible circuit electrodes described herein, a knife slot3722 is defined by the flexible circuit electrode 3702 to enable a knifeto reciprocate therealong. The electro optical sensor 3700 is disposedin one or more of the plurality of vias 3718.

FIG. 145 is a section view of the electro optical sensor 3700 integratedin a via 3718 of a flexible circuit electrode 3702 for sensing of tissueproperties, according to one aspect of the present disclosure. As shownin FIG. 145, the electro optical sensor 3700 is inserted inside a cavity3724 defined by the via 3718. The electro optical sensor 3700 iselectrically coupled to control circuitry by way of spring loadedelectrical contacts 3726 to conductive traces 3728 of the flexiblecircuit electrode 3702. An optically transparent window 3706 and isdisposed between an upper layer of an electrically insulative film 3716a and a lower layer of electrically insulative film 3716 b, where theupper and lower layers of electrically insulative materials 3716 a, 3716b can be made of polyimide, polyester, fluorocarbon, or any polymericmaterial, or any combinations thereof.

FIG. 146 is an elevation view of an end effector 3730 with a flexiblecircuit electrode 3702 comprising an electro optical sensor 3700integrated therewith, according to one aspect of the present disclosure.The end effector 3730 comprises an upper jaw member 3732 a and a lowerjaw member 3732 b. The flexible circuit electrode 3702 is disposed onthe lower jaw member 3732 b. A plurality of electro optical sensors 3700are disposed on the flexible circuit electrode 3702 located in the lowerjaw member 3732 b. Additionally, the electro optical sensors 3700 arepositioned on the flexible circuit electrode 3702 such that they extendabove the plane defined by the flexible circuit electrode 3702 and thuscan function as stop members to set a defined gap “G” between the upperand lower jaw members 3732 a, 3732 b when they are in a closedconfiguration.

FIG. 147 is a plan view of a flexible circuit electrode 3702 comprisinga plurality of electro optical sensors 3700 integrated with, accordingto one aspect of the present disclosure. A plurality of electro opticalsensors 3700 comprising photo diodes 3712 (see FIG. 143) are disposed onthe flexible circuit electrode 3702. Analog processing electroniccircuits 3734 to power and condition signals received from the photodiodes 3712 are located proximal to a tissue stop 3736. Traces 3738connect the analog processing electronic circuits 3734 to the digitalcontrol circuit 2402 (see FIG. 104 for details) located either in thehandle of the electrosurgical instrument or the generator 2404 (FIG.104).

With reference now to FIGS. 143-147, bipolar or monopolar RF surgicalinstruments may use various tissue parameters, such as impedance, todetermine the effect of RF electricity has had on the tissue. Providingadditional feedback to the generator can improve the confidence level tothe surgeon that a seal has been created in tissue bundles treated bythe end effector 3730 of the electrosurgical instrument.

The photo diodes 3712 disposed on the flexible circuit electrode 3702can be used to determine when the seal is complete, the location oftissue within the jaw members 3732 a, 3732 b (distal vs. proximal), andalso tissue type. The electro optical sensor 3700 can serve a secondarypurpose of setting the gap between the flexible circuit electrode 3702and the other jaw member or return electrode, which is shown as theupper jaw member 3732 a in FIG. 146. The electro optical sensor 3700 isincorporated into the flexible circuit electrode 3702 to determinechanges in tissue condition.

This disclosure illustrates how an electro optical sensor 3700 can beintegrated with a flexible circuit electrode 3702 for the purpose ofsensing tissue sensing in a monopolar or bipolar RF electrosurgicalinstrument. In one aspect, the electro optical sensor 3700 may be aninfrared (IR) photo diode 3712, however, other electro optical sensorsmay be used in a similar manner. The photo diode 3712 is mounted to thetrace layer of the flexible circuit electrode 3702 where individualconductors are photo etched from copper or another conductor. The photodiode 3712 is located in a distal portion of the flexible circuitelectrode 3702 such that the tissue being treated is within the opticalfield of view of the electro optical sensor 3700. Blood can be opticallymonitored based on the absorption of 350-600 nm light by hemoglobin inthe blood.

The photo diode 3712 is covered by an optical window 3706 selected forits transmission of wavelengths generating a large response in the photodiode 3712. The optical window 3706 may employ optical coatings toenhance transmission of the desired wavelengths while rejecting unwantedwavelengths. Coatings also may be used to enhance the durability of theoptical window 3706. The optical window 3706 also may includediffraction gratings 3708 or lenses 3710 to focus and furtherconcentrate photons from the tissue being treated. Traces 3714 of theflexible circuit electrode 3702 are connected to the photo diode 3712and routed proximally to carry the sensor current to analog processingelectronic circuits 3734. These processing electronic circuits 3734 mayconsist of pass band filters, amplifiers, and analog-to-digitalconverts. The most likely location for the analog electronics isproximal to the tissue stop 3736 such that they are within closeproximity to the electro optical sensor 3700, but do not interfere withthe treatment of tissue in the end effector 3730.

C. Flexible Circuit Electrode Including LED and Photodiode BasedVascular Sensor

FIG. 148 illustrates a flexible circuit electrode 3800 comprising avascular sensor 3802 comprising a LED 3804 and photodiode 3806arrangement integrated therewith for sensing vascularity, according toone aspect of the present disclosure. The vascular sensor 3802 utilizespairs of LEDs 3804 a, 3804 b, 3804 c and photodiodes 3806 a, 3806 b,3806 c to define multiple zones 1-3 in a jaw member of an end effectorto determine the vascularity of the tissue located in each of the zones1-3 for optimal tissue treatment. The vascular sensor 3802 iselectrically coupled to the control circuit 2402 (FIG. 104) to processthe signals provided by the vascular sensor 3802. Based on thevascularity sensed by the vascular sensor 3802, an algorithm can beselected by the control circuit 2402 to treat each of the zones 1-3 inan independent manner to enable better sealing and hemostasis. Thevascular sensor 3802 employs the pairs of LEDs 3804 a-3804 c andphotodiodes 3806 a-3806 c to sense the vascularity of the tissue withineach of the zones 1-3 in a manner similar to how a pulse oximeter works.Vascularity can be determined based on how much infrared or red light isabsorbed by blood in the tissue. Each of the zones 1-3 can then betreated independently by executing a unique algorithm to maximize tissuesealing and minimizing unintended damage for an optimal patient outcome.Blood can be optically monitored based on the absorption of 350-600 nmlight by hemoglobin in the blood.

D. Flexible Circuit Electrode Including Integrated Vascular TissueSensor

FIGS. 149-150 illustrate a vascular tissue sensor 3900 integrated with aflexible circuit electrode 3902, according to one aspect of the presentdisclosure. FIG. 149 is an end effector 3904 comprising upper and lowerjaw members 3906 a, 3906 b and a vascular tissue sensor 3900 integratedwith a flexible circuit electrode 3902, according to one aspect of thepresent disclosure. The upper jaw member 3906 a of the end effector 3904comprises the vascular tissue sensor 3900. The vascular tissue sensor3900 comprises a LED 3908 and a photo sensor 3910, such as a photodiode, for example. In addition, a visual LED 3912 is located on asurface of the upper jaw member 3906 a to indicate detection of vasculartissue. The lower jaw member 3906 b of the end effector 3904 comprises aflexible circuit electrode 3902. Electrical energy to power the vascularsensor 3900 elements is received by a first electrical conductiveelement 3914 and electrical energy to power the electrode 3902 isreceived by a second electrical conductive element 3916. The return path3918 is provided through electrically conductive portions of the upperjaw member 3906 a. The vascular tissue sensor 3900 configurationillustrated in FIG. 149 may be employed to detect vascular tissue to aidin anatomical identification and reduction of unintended tissue damage.

Remission phoupperlethysmography (PPG) is a technique that uses noninvasive monitoring of skin blood vessel pulsations. It is known thatmobile heart rate monitoring can be optically monitored based on theabsorption of 350-600 nm light by hemoglobin in the blood. The amount ofblood can be measured by irradiating a living body with light in thatwavelength range and measuring changes in the time needed for the lightto reflect back. Counting the number of rhythmic peaks in the amount ofblood gives the heart rate. A smart sensor for this application can becomposed of a green LED with 530 nm emission, a silicon photo diode, andappropriate circuits.

Based on the configuration illustrated in FIG. 149, a remission PPGmethod may be implemented using the LED 3912 and photo diode 3910, andappropriate circuits could be installed on the distal end in eitherupper or lower jaw members 3906 a, 3906 b of an RF bipolarelectrosurgical instrument and be used as a detection method to confirmthe presence of vascular tissue. For example, the vascular sensor 3900may electrically coupled to the control circuit 2402 (FIG. 104). ThisPPG circuit can be mounted to an independent layer of the flexiblecircuit electrode 3902 and can have its own geometric pattern to befitted in the upper or lower jaw member 3906 a, 3906 b and anindependent power/communication source to utilize the detection signal.

The detection signal could trigger the visual LED 3912 located on theupper jaw member 3906 a of the end effector 3904 and/or an audible tonefrom the generator 2404 (FIG. 104). Detection of vascular tissue couldthen be used to avoid unintended tissue damage, or to confirm thelocation of vessels and aid in anatomical identification. The PPGtechnology can integrated with the flexible circuit electrode 3902 toidentify vascular tissue and provide a signal to the end user and avoidunintended tissue damage and anatomical/vessel identification.

The LED 3908 and the photosensor 3910 can be located on a separate legof the flexible circuit electrode 3902 and can be connected to thedistal tip 3920 of the upper jaw member 3906 a to detect vascular tissueand provide a detection signal. The detection signal can be visual,audible, and/or vibratory to aid end user in use of the electrosurgicaldevice.

FIG. 150 is a schematic diagram of a sensor 3922 for mobile heart ratemonitoring, according to one aspect of the present disclosure. A smartsensor 3922 for this application comprises and LED 3924, a photodiode3926, and a processing circuit 3928 mounted on a substrate 3930. In oneaspect, the LED 3924 is a green LED with 530 nm emission and thephotodiode 3926 is a Silicon photodiode. The LED 3924 transmits a beamof light 3932 to the tissue 3934 and a portion of the light 3936 isreflected form the tissue 3934 and is detected by the photodiode 3926.The processing circuit 3928 control the operation of driving the LED3924 and processing the signal produced by the photodiode 3926 inresponse to detecting the reflected light 3936.

Heart rates can be optically monitored based on the absorption of350-600 nm light by hemoglobin in the blood. The amount of blood can bemeasured by irradiating a living body with light in that wavelengthrange from the LED 3924 and measuring changes in the time needed for thelight 3936 to reflect back using the photodiode 3926 and the processingcircuit 3928. Counting the number of rhythmic peaks in the amount ofblood gives the heart rate.

XVIII. Connection and Attachment Techniques for Flexible CircuitElectrodes A. Techniques for Connecting and Disconnecting FlexibleCircuits to Wiring on Re-Usable Instrument Connections

FIGS. 151-157 illustrate various attachment techniques to connect anddisconnect flexible circuits to wiring on re-usable instrumentconnections, according to one aspect of the present disclosure.Termination of the electrical signals of a flexible circuit can come inthe form of simple pins, holes, or fingers as shown in FIGS. 151-152where FIG. 151 illustrates a flexible circuit termination 4000comprising supported fingers 4002, according to one aspect of thepresent disclosure, and FIG. 152 illustrates a flexible circuittermination 4004 comprising unsupported fingers 4005, according to oneaspect of the present disclosure.

FIG. 153 illustrates an example flexible circuit electrode 4006 withfour supported fingers 4008 exposed on the proximal end 4010, accordingto one aspect of the present disclosure. The four supported fingers 4008could be inserted into a simple female connector 4012 as shown in FIG.154. In an alternate aspect, both of the two legs of the flexiblecircuit electrode can have two supported fingers instead of all four ona single leg, as shown above. This could be necessary due to the smallwidth of the electrode and the limitations of electrical connector size.

FIG. 154 is the frontside of a female electrical connector 4012configured to receive a flexible circuit electrode, according to oneaspect of the present disclosure, such as, for example, the flexiblecircuit electrode 4006 (FIG. 153). The connector 4012 has angledinternal side walls 4014 a, 4014 b to more easily receive the maleportion of the flexible circuit electrode 4006 during assembly, and fourbiased electrical retaining metallic contacts 4015 that are biased toensure electrical continuity is retained. FIG. 155 illustrates thebackside 4016 of the electrical connector 4012 shown in FIG. 154,according to one aspect of the present disclosure. The backside of theelectrical connector 4012 is soldered to wiring 4017 to connect toprocessing circuits such the control circuit 2402 (FIG. 104) and thegenerator 2404 (FIG. 104).

FIG. 156 is an internal section view of biased contacts 4018 of theconnector 4012 shown in FIG. 154 connected to the supported finger 4008shown in FIG. 153, according to one aspect of the present disclosure.The biased contacts 4018 connect to the supported finger 4008. FIG. 157is a full flexible circuit electrode assembly 4020 comprising theflexible circuit electrode 4006 shown in FIG. 153 connected to theconnector 4012 shown in FIG. 154, according to one aspect of the presentdisclosure.

B. Flexible Circuit Electrode Attachment Features for Connection andMechanical Attachment to Processing Circuits and Energy Sources

FIGS. 158-164 illustrate flexible circuit electrode attachment featuresfor connection and mechanical attachment to processing circuits andenergy sources, according to one aspect of the present disclosure. Usinga flexible circuit electrode on an RF electrosurgical instrument cansave space and reduce cost. The attachment/alignment features areconfigured to be attached and aligned the flexible circuit electrode tothe jaw members of an end effector. An RF electrosurgical instrumentcomprising a flexible circuit for an electrode may employattachment/alignment features soldered onto the flexible circuitelectrode for attachment to the jaw member, alignment on the jaw member,provide structural support, or make electrical connections.

FIG. 158 is a perspective view of a flexible circuit electrode 4100 withattachment/alignment features 4102 provided on a surface 4104 thereon,according to one aspect of the present disclosure. Theattachment/alignment features 4102 are soldered to the flexible circuitelectrode 4100 to facilitate attachment of the flexible circuitelectrode 4100 to a jaw member, such as, the jaw member 4106 shown inFIG. 159. The attachment/alignment features 4102 could be multiple partsor a single hook that fits into a slot on the jaws. It could also besoldered on electrical connectors. A knife slot 4103 is provided in theflexible circuit electrode 4100 to enable the knife to reciprocatetherealong.

FIG. 159 is a section elevation view of a lower jaw member 4106 with theflexible circuit electrode 4100 shown in FIG. 158 withattachment/alignment features 4102 shown in FIG. 158 prior to beingdisposed thereon, according to aspect of the present disclosure. Thelower jaw member 4106 comprises a plurality of recesses 4107 sized andconfigured to receive the attachment/alignment features 4102 attached tothe flexible circuit electrode 4100.

FIG. 160 is a section view of the lower jaw member 4106 shown in FIG.159 with the flexible circuit electrode 4100 with theattachment/alignment features 4102 shown in FIG. 159 prior to beingdisposed thereon, according to aspect of the present disclosure.

FIG. 161 is a partial perspective view of the flexible circuit electrode4100 disposed shown in FIG. 158 disposed on an insulative flexiblesubstrate 4105 with a solder point 4108 for connecting theattachment/alignment feature 4102 shown in FIG. 158 to the flexiblecircuit electrode, according to one aspect of the present disclosure;

FIG. 162 is an exploded view of the flexible circuit electrode 4100 withmultiple attachment/alignment features 4102 shown removed from theflexible circuit electrode 4100, according to aspect of the presentdisclosure. The attachment/alignment features 4102 are soldered tosolder points 4108 formed on the substrate of the flexible circuitelectrode 4100.

FIG. 163 is an exploded view of a flexible circuit electrode with asingle attachment/alignment feature 4110 shown removed from the flexiblecircuit electrode 4112, according to aspect of the present disclosure. Aknife slot 4113 is provided in the flexible circuit electrode 4112 toenable the knife to reciprocate therealong.

FIG. 164 is a perspective view of a flexible circuit electrode 4114comprising an attachment feature 4116 for a wire/cable connector 4118,according to one aspect of the present disclosure.

C. Flexible Circuit Electrode Including Alternate Contacts for Routingand Wring Multiple Electrode Paths to Monopolar or Bipolar Instruments

FIGS. 165-173 illustrate a flexible circuit electrode includingalternate contacts for routing and wiring multiple electrode paths tomonopolar or bipolar instruments for spot coagulation, according to oneaspect of the present disclosure. A flexible circuit electrode with themain electrode formed on an upper surface and multiple electrode pathsformed on a lower surface can be used for monopolar or bipolar RF spotcoagulation. These paths can run lengthwise along the flexible circuitelectrode back to the handle of the electrosurgical instrument. Theflexible circuit electrode can be coiled around a tube in the handlewith rings to transmit the RF energy. A flexible circuit electrode foran RF electrosurgical instrument is provided where one surface of thecircuit is an RF sealing surface of exposed metal and another surface isthe same or a different exposed electrode or electrodes in an area thatis not the main sealing surface. A flexible circuit electrode isprovided with an electrode surface where the flexible circuit electrodeterminates in a handle of the electrosurgical instrument where thecircuit forms rings to transmit RF through a rotating contact. Thesevarious aspects are described hereinbelow.

FIG. 165 is a perspective view of an end effector 4200 comprising anupper and lower jaw member 4202 a, 4202 b comprising a flexible circuitelectrode 4204 with a distal monopolar electrode 4206 and lateralbipolar electrodes 4208 a, 4208 b, 4208 c, according to one aspect ofthe present disclosure. By using a flexible circuit and printing themain electrode 4204 on the surface and using the lower of the flexiblecircuit multiple electrode paths for monopolar or bipolar spotcoagulation can be used. These paths can run along the flexible circuitback to the handle of the electrosurgical instrument. The distalmonopolar electrode 4206 and the lateral bipolar electrodes 4208 a-4208c are electrically connected to the control circuit 2402 (FIG. 104) andthe generator 2404 (FIG. 104). A knife slot 4210 is provided in thelower jaw member 4202 b and the flexible circuit electrode 4204 toenable the knife to reciprocate therealong.

FIG. 166 is a plan view of the flexible circuit electrode 4204 shown inFIG. 165, according to one aspect of the present disclosure. Theflexible circuit electrode 4204 is shown unfolded showing both sides ofthe lateral bipolar electrode 4208 a-4208 c and the distal monopolarelectrode 4206. Details of the electrically conductive traces at theproximal end 4212 of the flexible circuit electrode 4204 are shown inFIG. 167.

FIG. 167 is a detail section view of the proximal end of the flexiblecircuit electrode 4204 shown in FIG. 166 showing the electricallyconductive traces 4214 a, 4214 b, 4214 c which are electrically coupledto the lateral bipolar electrodes 4208 a, 4208 b, 4208 c andelectrically conductive trace 4215 which is electrically coupled to thedistal monopolar electrode 4206, according to one aspect of the presentdisclosure.

FIG. 168 is a perspective view of a lower jaw member 4216 of a jawassembly comprising a fold over flexible circuit electrode 4218,according to one aspect of the present disclosure. A knife slot 4220 isprovided in the fold over flexible circuit electrode 4218 to enable theknife to reciprocate therethrough.

FIG. 169 is a detail view of the fold over flexible circuit electrode4218 shown in FIG. 166, according to one aspect of the presentdisclosure. The flexible circuit electrode 4218 comprises exposedlateral sealing surfaces 4222 a, 4222 b and an upper main sealingsurface 4222 c. The sealing surfaces 4222 a-4222 c are exposed metalelectrodes that are sized and configured to conduct RF electricity thatcontact tissue and provide sealing surfaces.

FIG. 170 is a perspective view of a rotating contact assembly 4230disposed about the outer surface 4234 of an inner tube 4236 of a shaftcomponent of the electrosurgical instrument, according to one aspect ofthe present disclosure. The rotating contact assembly 4230 is formed ona flexible circuit 4232 that is coupled to the electrode. The flexiblecircuit 4232 terminates in a handle of the electrosurgical instrumentwhere the circuit forms rings such as a plurality of rotating contacts4236 a, 4236 b, 4236 c, 4236 d configured to transmit RF electricalenergy through the rotating contact assembly 4230. The flexible circuitcan be coiled around the inner tube 4236. FIG. 1A illustrates a shaft 10of an electrosurgical instrument 2. The inner tube 4236 is typicallydisposed within the shaft 10. Turning back to FIG. 170, in one aspectthe rotating contact assembly 4230 comprises a plurality of rotatingcontacts 4236 a-4236 d formed on the flexible circuit 4232 and disposedabout the inner tube 4236, for example. An exposed electricallyconductive element 4238 (e.g., copper) is located behind the pluralityof rotating contacts 4236 a-4236 d and is adhered about the outersurface 4234 of the inner tube 4236 and extends distally towards the jawassembly or end effector.

With reference now also to FIG. 170, FIG. 171 is a detail section viewof electrical contact wipers 4240 a, 4240 b, 4240 c, 4240 d electricallyand rotatably coupled to the plurality of rotating contacts 4236 a-4236d of the rotating contact assembly 4230 disposed about the outer surface4234 of the inner tube 4236, according to one aspect of the presentdisclosure.

FIG. 172 is a perspective view of the rotating contact assembly 4230,according to one aspect of the present disclosure. FIG. 173 is aperspective view of the rotating contact assembly 4230 comprising anouter tube 4242, an inner tube 4236, and a plurality of rotatingcontacts 4236 a-4236 d formed on a flexible circuit electrode anddisposed about the inner tube 4236, according to one aspect of thepresent disclosure. The rotating contact assembly 4230 is rotatablydisposed within the outer tube 4242.

D. Flexible Circuit Including Snap in Electrode Assembly andGrasping/Gap Setting Elements at a Distal End

FIGS. 174-176 illustrate flexible circuit 4300 comprising a snap inelectrode assembly 4302 and grasping/gap setting elements 4304 at adistal end 4306, the elements having various geometries to aid ingrasping and setting the gap “G” between the upper jaw member 4308 a andthe lower jaw member 4308 b members of a clamp jaw assembly 4310, and aconnecting scheme to couple the snap in electrode assembly 4302 to theclamp jaw assembly 4310, according to one aspect of the presentdisclosure. The flexible circuit 4300 comprising the snap in electrodeassembly 4302 is a replaceable component and can provide multipleoptions of clamp assemblies for an electrosurgical instrument duringmanufacturing. The interchangeable configuration provides various levelsof grasping (i.e., atraumatic for liver or general surgery) and variouslevels of gap setting features for marching versus sealing. The proximalend 4314 of the interchangeable flexible circuit 4300 electrodecomprises an edge connector 4312 that contains an identification cardsuch that control circuit can identify the type of flexible circuit 4300connected to the shaft 4316 of the electrosurgical instrument.

FIG. 174 is a perspective view of a flexible circuit 4300 comprising asnap in electrode assembly 4302 at a distal end 4306 and an edgeconnector 4312 that contains an identification card at a proximal end4314, according to one aspect of the present disclosure. The snap inelectrode assembly 4302 comprises multiple layers. An upper layer 4318is an electrically conductive layer 4326 that act as the electrode toapply energy to tissue located in the clamp jaw assembly 4310. Theelectrode 4326 comprises a plurality of elements 4304 printed thereon toprovide various gaps or to various grasping features. The middle layer4320 provides the electrical connection to the circuitry back to theedge connector 4312. A lower layer 4322 is an overmolded component thatconnects via snap features 4306 to the lower jaw member 4308 b of theclamp jaw assembly 4310. The snap fit features 4306 are formed onlateral surfaces of the snap in electrode assembly 4302 to snap fitconnect the electrode assembly 4302 to snap fit features 4338 to thelower jaw member 4308 b (FIG. 176). The edge connector 4312 comprises anidentification circuit element such that the control circuit canidentify the type of flexible circuit 4300 connected to the shaft 4316of the device. A knife slot 4336 is provided in the snap in electrodeassembly 4302

FIG. 174A is a detail view of two types of elements 4304, according tovarious aspects of the present disclosure. A first type of elements 4332terminate in a pointed edge. As second type of elements 4334 terminatein a flat edge. The elements 4332, 4334 are configured to set a gap “G”between the upper and lower jaw members 4308 a, 4308 b of the clamp jawassembly 4310 (FIG. 176).

FIG. 175 is a section view of the proximal end 4314 of the flexiblecircuit 4300 taken along section line 175-175, as shown in FIG. 174,showing a T-slot 4328 configuration for alignment of the flexiblecircuit 4300 with the shaft 4316 (FIG. 176) of the electrosurgicalinstrument, according to one aspect of the present disclosure.

FIG. 176 is an elevation view of the clamp jaw assembly 4310 showing thefemale end of an edge connector 4330 located on the shaft 4316 forelectrically and mechanically coupling the edge connector 4312 of theflexible circuit 4300 (FIG. 174) to a control circuit and/or agenerator, according to one aspect of the present disclosure. Snap fitfeatures 4338 are sized and configured to receive the snap fit features4306 formed on the lateral surfaces of the snap fit electrode assembly4302 (FIG. 174). The snap fit features 4306, 4338 mechanically connectthe snap in electrode assembly 4302 to the lower jaw member 4308 b ofthe clamp jaw assembly 4310.

XIX. Automatic Electrode Renewal System for Flexible Circuit Electrodes

FIGS. 177-178 illustrate an automatic electrode renewal system 4400 forflexible circuit electrodes, such as spools of flexible circuitelectrodes 4404 a, 4404 b wind about corresponding rollers 4406 a, 4406b, according to one aspect of the present disclosure. FIG. 177 is anelevation view of a clamp jaw assembly 4407 comprising an upper jawelement 4414 a and a lower jaw element 4414 b and a renewable flexiblecircuit electrode system 4400 for unwinding and advancing clean flexiblecircuit electrodes 4404 a, 4404 b from a proximal end 4408 pair of upperand lower rollers 4406 a, 4406 b and winding used flexible circuitelectrodes about a distal end 4410 pair of upper and lower spools 4412a, 4412 b in a distal direction 4422 a, 4422 b, according to aspect ofthe present disclosure. The flexible circuit electrodes 4404 a, 4404 bcan be automatically fed into contact with tissue. In one aspect, theflexible circuit electrodes 4404 a, 4404 b can be configured for aspecific tissue type also can be fed to be in contact with the specifictissue type.

A pair of upper and lower spools 4406 a, 4406 b of clean flexiblecircuit electrodes 4404 a, 4404 b is located at the proximal end 4408 ofthe clamp jaw assembly 4407 and a pair of upper and lower rollers 4412a, 4412 b of used flexible circuit electrodes is located as the distalend 4410 of the clamp jaw assembly 4407. As the flexible circuitelectrodes 4404 a, 4404 b are used, clean electrodes can be advanced ina counterclockwise direction 4416 a and a clockwise direction 4416 b bywinding the used electrodes at the distal rollers 4412 a, 4412 b andunwinding clean electrodes from the proximal rollers 4406 a, 4406 b.

To provide a clean electrode, the rollers 4406 a, 4406 b, 4412 a, 4412 bare rotated to expose tissue to a new electrode surface. Thisconfiguration enables the use of different sections of a surface of theflexible circuit electrodes 4404 a, 4404 b to treat different types oftissue. This technique can provide a specialized electrode type fordifferent tissues. This technique also can eject tissue from the jawmembers 4414 a, 4414 b to create a peeling release as opposed to ashearing release.

FIG. 178 is an elevation view of the automatic electrode renewal system4400 shown in FIG. 177 comprising an electrical brush contact 4420 toelectrically couple to a flexible circuit electrode 4404 a disposedabout the lower roller 4406 b at the proximal end 4408, according to oneaspect of the present disclosure. Although the upper roller 4406 a (FIG.177) is not shown in FIG. 178, a similar brush contact 4420 may becoupled to the flexible circuit electrode 4404 a disposed about theupper roller 4406 a at the proximal end 4408. The electrical contact forthe upper and lower spools 4406 a, 4406 b of flexible circuit electrodes4404 a, 4404 b can be provided by brush contacts or the rollers 4406 a,4406 b. The rollers 4406 a, 4406 b can be used as electrical contactprovided between the flexible circuit electrodes 4404 a, 4404 b and thestructural support portion of the clamp jaw assembly 4407.

XX. Flexible Circuit Electrode Including Vibratory Elements to MitigateTissue Sticking to the Clamp Jaw Members A. Vibratory Element IncludingVibrating Piezoelectric Bimorph Transducer to Release Tissue from theJaw Members

FIGS. 179-184 illustrate a flexible circuit comprising an electrode anda vibratory element to mitigate tissue sticking to the clamp jawmembers, according to one aspect of the present disclosure. Thevibratory element comprises a piezoelectric bimorph transducer thatvibrates to release tissue from the jaw members of the clamp jawassembly. During use, tissue adheres to the electrode surface in RFelectrosurgical instruments. Vibrations, e.g., acoustic energy, can beemployed to release the tissue from the electrode surface. Vibratoryenergy can be applied in proportion to the amount of tissue stickingseen thereby not treating the tissue with acoustic energy if it is notnecessary.

Vibratory energy can be used to release tissue from the surface of aflexible circuit electrode. However, acoustic vibration also can damagetissue and or the tissue seal if it is not necessary. In one technique,acoustic energy is applied in proportion to the sticking forceexperienced when opening the jaws. For example, if no sticking force isdetected, then no acoustic vibration is applied and if a high stickingforce is detected, then high acoustic vibration is applied.Piezoelectric bimorph transducers that are 180° out of phase are placedin the upper and lower jaws. Flexible circuit electrodes can bend withthe piezoelectric bimorph transducers.

FIG. 179 is a section view of a piezoelectric bimorph transducer 4500attached to a flexible circuit electrode 4502, according to one aspectof the present disclosure. The piezoelectric bimorph transducer 4500comprises a metal layer 4504 sandwiched between two piezoelectric layers4506 a, 4506 b. In one aspect, the piezoelectric layers 4506 a, 4506 bmay be lead zirconate titanate, an intermetallic inorganic compound withthe chemical formula Pb[ZrxTi1-x]O3 (0≦x≦1). Also called PZT, it is aceramic perovskite material that shows a marked piezoelectric effect,meaning that the compound is used in a number of practical applicationsin the area of electroceramics. In one aspect, the metal layer 4504 maycomprise brass, or other metal. The first piezoelectric layer 4506 a isdriven by a first high voltage time varying signal v1 and the secondpiezoelectric layer 4506 b is driven by second high voltage time varyingsignal v2 that is 180° out of phase relative to the first high voltagetime varying signal v1.

FIG. 180 is a schematic illustration of the displacement of thepiezoelectric bimorph transducer 4500 shown in FIG. 179, where a firstmode of deflection is shown in solid line 4508 and a second mode ofdeflection is shown in dashed line 4510, according to one aspect of thepresent disclosure. Accordingly, with the end portions 4512 a, 4512 b ofthe piezoelectric bimorph transducer 4500 are anchored, thepiezoelectric layers 4506 a, 4506 b are electrically activated to causeone piezoelectric layer 4506 a to extend and the other piezoelectriclayer 4506 a layer to contract. This may be implemented by driving onepiezoelectric layer 4506 a with a first high voltage time varying signaland driving the other piezoelectric layer 4506 b with a second highvoltage time varying signal that is 180° out of phase relative to thefirst high voltage time varying signal. The total displacement isindicated as “D”. Repeated electrical actuation causes the piezoelectricbimorph transducer 4500 to vibrate or oscillate. This technique can beuse to vibrate the flexible circuit electrode 4502 to release any tissuestuck to the electrode 4502 during the sealing process.

FIG. 181 is a section view of a clamp jaw assembly 4514 comprising upperand lower bimorph transducers 4500 a, 4500 b located in respective upperand lower jaw members 4516 a, 4516 b, according to one aspect of thepresent disclosure. A layer of rubberized polymer 4518 a is attached tothe upper jaw member 4516 a. A bimorph transducer 4500 a is attached tothe rubberized polymer 4518 a on one side and to a flexible circuitelectrode 4502 a on the other side. Similarly, a layer of rubberizedpolymer 4518 b is attached to the lower jaw member 4516 b. A bimorphtransducer 4500 b is attached to the rubberized polymer 4518 b on oneside and to a flexible circuit electrode 4502 b on the other side. Asshown in FIG. 181, the bimorph transducers 4500 a, 4500 b are in thefirst mode 4508 (FIG. 180) of maximum deflection. The upper and lowerbimorph transducers 4500 a, 4500 b located in the clamp jaw assembly4514 oscillate between the first mode 4508 and second mode 4510 ofdeflection, as shown in FIG. 180, to release tissue.

FIG. 182 is a section view of the clamp jaw assembly 4514 shown in FIG.181, where the bimorph transducers 4500 a, 4500 b located in therespective upper and lower jaw members 4516 a, 4516 b are in the secondmode 4510 of maximum deflection (FIG. 180), according to one aspect ofthe present disclosure.

FIG. 183 is a section view of the lower bimorph transducer 4500 blocated on a lower jaw member 4516 b of the clamp jaw assembly 4514configured in sensor mode to measure the adhesion force “F” of tissuesticking to the lower jaw member 4516 b, according to one aspect of thepresent disclosure. Although not shown in FIG. 183, the same techniqueapplies to measuring the adhesion force F tissue sticking to the upperjaw member 4516 a using the upper bimorph transducer 4500 a. It is knownthat a bimorph piezoelectric transducer can operate in actuator mode andsensor mode. In actuator mode, a voltage applied to the transducercauses the transducer to displace and in sensor mode, displacement ofthe transducer generates a voltage. The bimorph transducer 4500 can beoperated in sensor mode to measure the sticking force F. The stickingforce “F” drives the bimorph transducer 4500 in the second mode ofdeflection. The sticking force “F” shows the displacement “d” of thelower bimorph transducer 4500 b due to tissue sticking to the lowerflexible circuit electrode 4502 b and to the upper flexible circuitelectrode 4502 a (not shown) or simply sticking to the upper jaw member4516 a (not shown).

Accordingly, the bimorph transducer 4500 can become a force sensor whenforce is applied to it. The bimorph transducer 4500 can produce avoltage under a sticking load. The bimorph transducer 4500 can beconfigured to switch between a force measuring bimorph sensor and adriving bimorph transducer to result in mechanical vibrations that areproportional to the sticking force “F”. The mechanical vibrations may beemployed in proportion to the adhesion force “F” of the tissue stickingto the electrode 4502.

FIG. 184 is a logic flow diagram 4520 of a technique for operating abimorph transducer by switching between a force measuring bimorph sensorto a driving bimorph transducer resulting in vibrations proportional tothe adhesion force, according to one aspect of the present disclosure. Acontrol circuit, such as the control circuit 2402 shown in FIG. 104, canbe programmed and configured to execute an algorithm to implement thelogic flow diagram 4520. Accordingly, the control circuit 2402 isconfigured to stop driving the bimorph element 4500 a, 4500 b andmeasure 4522 the voltage (v) on the bimorph element 4500 a, 4500 b,where the voltage (v) is proportional to the tissue adhesion force “F”on the flexible circuit electrode 4502 as described in connection withFIG. 183. The control circuit 2402 then drives 4524 the bimorph element4500 a, 4500 b in proportion to the measured voltage (v) according tothe function P=f(v) for a period of time “t” and the cycle is repeated apredetermined frequency selected from the range of 100 Hz to 1000 Hz, or250 Hz to 750 Hz, or preferably approximately 500 Hz. Thus, the controlcircuit 2402 vibrates or oscillates the bimorph element 4502 a, 4502 bin proportion to the tissue adhesion force “F”. The total work done bythe bimorph element 4500 a, 4500 b to release the tissue adhered to theflexible circuit electrode 4502 can be represented by the followingequation:

w=∫ ₀ ^(t) f(v)dt  (6)

where w is work defined by the integral over the period “t” of f(v).

B. Flexible Circuit Electrode Including a Vibratory Element Configuredto Vibrate to Reduce Tissue Adhesion on Electrode or Remove TissueAdhered to Electrode

FIGS. 185-186 illustrate a jaw member 4700 comprising a flexible circuitelectrode assembly 4702 comprising a vibratory element configured tovibrate to reduce tissue adhesion on an electrode 4704 or remove tissueadhered to the electrode 4704, according to one aspect of the presentdisclosure. FIG. 187 illustrates a circuit configured to actuate thevibratory element, according to one aspect of the present disclosure.

FIG. 185 is a plan view of a vibrating jaw member 4700 comprising aflexible circuit electrode assembly 4702 configured to vibrate to reducetissue adhesion to the electrode 4704 or remove tissue adhered to theelectrode 4704, according to one aspect of the present disclosure. FIG.186 is a section view of the vibrating jaw member 4700 shown in FIG. 185taken along section 186-186, according to one aspect of the presentdisclosure. During sealing/fastening/adhering tissue together betweenbipolar jaw members of an electrosurgical instrument, the tissueaffected has a tendency to stick to one or both jaw members.Accordingly, the vibrating jaw member 4700 provides a laminated groovedflexible circuit electrode assembly 4702 disposed across an uppersurface 4716 of one of the two jaw members 4700. As shown in FIG. 186,the flexible circuit electrode assembly 4702 is positioned on upperportion of a sheet of piezoelectric element 4712, which may be in theform of a sheet, that when energized will create vibrations anddisplacement of the flexible circuit electrode assembly 4702, which inturn will reduce sticking of tissue to the flexible circuit electrode4704. Alternatively, if sticking occurs, actuation of the piezoelectricelement 4712 will loosen the stuck tissue. A knife slot 4724 is providedto enable a knife to reciprocate therealong.

With reference still to FIGS. 185-186, the flexible circuit electrodeassembly 4702 is disposed over the jaw member 4700 of a clamp jawassembly of an electrosurgical instrument. The jaw member 4700 mayrepresent either an upper jaw member or a lower jaw member of the clampjaw assembly. The flexible circuit assembly 4702 may be attached to theupper jaw member, lower jaw member, or both. The flexible circuitelectrode assembly 4702 comprises a first flexible electricallyinsulative substrate 4714 (e.g., polyimide, polyester, fluorocarbon, orany polymeric material, or any combinations thereof), and insulator 4706disposed over the insulative substrate 4714, and conductive traces orpads (e.g., copper) formed on the insulator 4706. The conductive tracesdefine the electrode 4704. A second flexible electrically insulativesubstrate 4710 is disposed over the insulator 4706 except where theelectrode 4704 is exposed to enable tissue treatment, where a groove4711 is defined between the electrodes 4704 and the second flexibleelectrically insulative substrate 4710.

A piezoelectric element 4712 (e.g., transducer) is laminated on a lowersurface 4715 of the first flexible electrically insulative substrate4714 of the flexible circuit electrode assembly 4702. The piezoelectricelement 4712 is positioned on upper of the jaw member 4700 body 4726,which may be a rigid structure. Thus, when used with anotherarmature/jaw member in opposing position and then actuated towards eachother, they will clamp and hold tissue therebetween. The electrode 4704may be energized in bipolar or monopolar RF mode. The piezoelectricelement 4712 can be actuated by a circuit 4718, as described in moredetail in connection with FIG. 187.

FIG. 187 is a schematic diagram of a circuit 4718 configured to activatethe flexible circuit electrode assembly 4702 (FIGS. 185-186) and thepiezoelectric element 4712 (FIG. 186) simultaneously, according to oneaspect of the present disclosure. The circuit 4718 is configured toactuate the piezoelectric element 4712 and the electrode 4708 (FIGS.185-186) at the same time. The circuit 4718 comprises an energy source4720 configured to provide a high voltage alternating current voltage.The energy source 4720 is applied to the electrode 4708 to treat tissue.A sub-circuit 4722 is used to drive the piezoelectric element 4712.

In other aspects, the electrode 4708 may be energized separately usingtwo separate circuits, one to energize the piezoelectric element 4714and one to energize the electrode 4708. In another aspect, a singlecircuit may be used to apply power between the piezoelectric element4714 and the electrode 4708 alternately rather than simultaneously toaffect tissue in the jaw members. In other aspects, power may be appliedto the piezoelectric element 4714 and the electrode 4708 to affecttissue in different ways.

XXI. Flexible Circuit Electrodes for Therapy, Sensing, Power, andProximity Detection

FIGS. 188-189 illustrate a jaw member 4600 of clamp jaw assemblycomprising a flexible circuit 4602 comprising an inner electrode 4604for applying therapy to tissue and an outer electrode 4608 for sensing,powering accessory functions, and proximity detection among otherfunctions, according to one aspect of the present disclosure. Thesefunctions include: visualizing the tip of the jaw member 4600 vialighting, confirming that the jaw member 4600 has engaged the tissue,determining the presence of tissue in the jaw member 4600, determiningwhere tissue is located in the jaw member 4600, and determining whethera nerve tissue is present in close proximity to the jaw member 4600

FIG. 188 is a perspective view of a jaw member 4600 comprising aflexible circuit 4602 comprising an inner electrode 4604 and an outerelectrode 4608, according to one aspect of the present disclosure. Theinner electrode 4604 is disposed on and defines a tissue graspingsurface 4606 of the jaw member 4600. The inner electrode 4604 isconfigured to apply therapeutic levels of energy to tissue to sealand/or coagulate tissue. The outer electrode 4608 is disposed on anouter rim 4610 of the jaw member 4600. The outer electrode 4608 isconfigured to sense and power accessory functions.

FIG. 189 is a detail view of the jaw member 4600 shown in FIG. 188,according to one aspect of the present disclosure. As shown in FIG. 189,the flexible circuit 4602 comprises a fist electrically insulative layer4616 (e.g., polyimide, polyester, fluorocarbon, or any polymericmaterial, or any combinations thereof) attached to the jaw member 4600structure. The outer electrode 4608 is disposed over the fist insulativelayer 4616. A second electrically insulative layer 4618 (e.g.,polyimide, polyester, fluorocarbon, or any polymeric material, or anycombinations thereof) is disposed over the outer electrode 4608. Theinner electrode 4604 is disposed over the second insulative layer 4618and defines the tissue grasping surface 4606 comprising a knife slot4620 to enable a knife to reciprocate therein. The flexible circuit 4602may be disposed over the upper jaw member, lower jaw member, or both, ofa clamp jaw assembly.

With reference now to FIGS. 188 and 189, in one aspect, the outerelectrode 4608 disposed on the outer rim 4610 of the jaw member 4600 isconfigured to sense and power accessory functions such as providingdirect current (DC) voltage to power LEDs when both upper and lower jawscontact electrically conductive media, detecting tissue presence in thejaw member 4600, the distal end 4612 of the jaw member 4600, theproximal end 4614 of the jaw member 4600. The outer electrode 4608 alsois configured to apply DC biphasic power for nerve stimulation. Agrounding pad may be employed to complete the circuit with the inner orouter electrodes 4604, 4608.

XXII. Lighting and Illuminating A. Flexible Circuit Electrode IncludingLEDS for Illuminating Tissue

FIGS. 190-192 illustrate a flexible circuit electrode assembly 4804comprising electrodes 4806 for tissue treatment and LEDs 4808 forilluminating tissue, according to one aspect of the present disclosure.In one aspect, the LEDs 4808 can be provided on the periphery of theflexible circuit electrode assembly 4804 to provide visualization at thesurgical site. A layer may be added to the flexible circuit electrodeassembly 4804 where the LEDs 4808 are printed/connected along theperiphery thereof to emit light at the surgical site. A separate powersource for the LED 4808 from the flexible circuit electrode 4806 permitslighting at all times and adds another functional feature for the enduser to increase their visualization.

FIG. 190 is an elevation view of a clamp jaw assembly 4800 comprising anupper jaw member 4802 a and a lower jaw member 4802 b comprising aflexible circuit electrode assembly 4804 in the lower jaw member 4802 b,according to one aspect of the present disclosure. The upper and lowerjaw members 4802 a, 4802 b are movable relative to each such that eitherthe upper or lower jaw member 4802 a, 4802 b is movable or both aremovable. The flexible circuit electrode assembly 4804 comprises anelectrode 4806 and a plurality of LEDs 4808 positioned around theperiphery of the lower jaw member 4802 b.

FIG. 191 is a plan view of the flexible circuit electrode assembly 4804comprising the electrode 4806 and the plurality of LEDs 4808 positionedaround the periphery of the lower jaw member 4802 b, according to oneaspect of the present disclosure. The LEDs 4808 may be printed along theperimeter or periphery 4816 of the flexible circuit electrode assembly4804. Power to the electrode 4806 is provided by a first electricalconductive element 4810 and power to the LEDs 4808 is provide by asecond electrical conductive element 4812. The conductive elements 4810,4812 are coupled to the control circuit 2402 and/or the generator 2404(FIG. 104). A knife slot 4814 is provided to enable a knife toreciprocate therealong.

To provide improved visualization at the surgical site and to reducerisk of inadvertent tissue damage, the flexible circuit electrodeassembly 4804 can be constructed in multiple layers of conductive andinsulating materials. On one such layer LEDs 4808 can be embedded alongthe outer edge 4816 of the flexible circuit electrode assembly 4804 oron the entire conductive layer 4818 to provide illumination directly atthe surgical site where the jaws of the clamp jaw assembly 4800 (FIG.190) of the electrosurgical instrument. A company that produces suchLEDs 4808 is Rohinni, which produces LEDs 4808 using diodes about thesize of a red blood cell. The LED 4808 light layer may be supplied itsown power source through the second conductive element 4812 to provideillumination 100% of the time thus adding a level of additionalfunctionality to the device as a visualization tool. The electrode 4806can be powered with an independent power source through the firstelectrically conductive element 4810.

FIG. 192 is a section view of the flexible circuit electrode assembly4804 taken along section line 192-192 as shown in FIG. 191, according toone aspect of the present disclosure. The flexible circuit electrodeassembly 4804 comprises conductive layers 4820 (e.g., copper) betweenthe electrically insulative layers 4822 (e.g., polyimide, polyester,fluorocarbon, or any polymeric material, or any combinations thereof).The electrode 4806 is the exposed conductor layer on upper of theflexible circuit electrode assembly 4804. The LEDs 4808 are locatedabout the periphery 4816 of the flexible circuit electrode assembly4804.

B. Flexible Circuit Electrode Including LED for Signaling Status

FIGS. 193-194 illustrate a flexible circuit electrode assembly 4904comprising an electrode 4906 and an LED 4908 for signaling status,according to one aspect of the present disclosure. FIG. 193 is aperspective view of a clamp jaw assembly 4900 comprising an upper jawmember 4902 a and a lower jaw member 4902 b and a flexible circuitelectrode assembly 4904, according to one aspect of the presentdisclosure. The upper and lower jaw members 4902 a, 4902 b are movablerelative to each such that either the upper or lower jaw member 4902 a,4902 b is movable or both are movable. An LED section 4910 of theflexible circuit electrode assembly 4904 comprises a plurality of LEDs4908 to provide improved visualization at the surgical site. The LEDsection 4910 is positioned in the upper jaw member 4902 a and theelectrode 4906 is located in the lower jaw member 4902 b to providevisual indication of tissue sealing status. Signaling at the surgicalsite enables the surgeon to see the LED signal without having to look atthe device outside the surgical site. Power and communication to the LEDsection 4910 is provided through a first conductive element 4914 andpower to the electrode 4906 is provided through a second conductiveelement 4916. The conductive elements 4914, 4916 are coupled to thecontrol circuit 2402 and/or the generator 2404 (FIG. 104). A knife slot4912 is provided to enable a knife to reciprocate therealong.

In one aspect, the LEDs section 4910 comprises colored LEDs 4908. In oneaspect, three LEDs 4908 are provided. A red LED 4908 a, a yellow LED4908 b, and a green LED 4908 c, for example. Additional or fewer LEDs4908 may be employed as well as different colors. The colored LEDs 4910provided on a separate leg of the flexible circuit electrode assembly4904 can be connected back to a control circuit 2402 or generator 2404(FIG. 104). The red LED 4908 a/yellow Led 4908 b/green LED 4908 c on theupper jaw member 4902 a may be combined with tones to indicate differentconditions at the surgical site. Visualization can be linked to othersensor feedback such as tissue status via temperature, photo optics, jawposition, among others. Improved visual communication at the surgicalsite provides consistent tissue performance and improved communicationto user of device status—generator status and tissue status.

FIG. 194 is a plan view of the flexible circuit electrode assembly 4904shown in FIG. 193, according to one aspect of the present disclosure.The flexible circuit electrode assembly 4904 comprises two sections, anelectrode section 4918 and an LED section 4910 such that the LED section4910 can be located in one jaw member and the electrode section 4918 canbe located in the other jaw member. The LED section 4910 comprises afirst group of colored LEDs 4908: red LED 4908 a, a yellow LED 4908 b,and a green LED 4908 c on one side, and a second group of colored LEDS4908′: red LED 4908 a′, a yellow LED 4908 b′, and a green LED 4908 c′ onthe other side to provide added visibility of the LEDS signals to thesurgeon. The conductive elements 4914, 4916 coupled to the electrode andLED section 4910 on one side and the control circuit 2402 and/or thegenerator 2404 (FIG. 104) on the other and the knife slot 4912 are alsoshown.

With reference now to FIGS. 193 and 194, the flexible circuit electrodeassembly 4904 can be constructed in multiple layers of conductive andinsulating materials and each layer may have different geometricalpatterns and different power sources. On one such layer, independent ofthe electrode 4906, may comprise the colored LED 4908 lights embeddedalong the periphery 4920 and can extend in such a way that it may berouted and secured into the jaw member 4902 a, 4902 b of a monopolar orbipolar RF electrosurgical instrument that is opposite to the jaw member4902 a, 4902 b that contains the electrode 4906. The LED 4908 layer canhave its own power/communication source through conductive element 4916linked back to the control circuit 2402 and/or the generator 2404 (FIG.104). The colored lighting would provide a visual signal in the surgicalfield and would not require the user to move their focus outside of thesurgical field. The colored lighting could be synced to communicate thepower state of the electrosurgical instrument, including tones, or othersensor feedback driven tissue status updates related to temperature,photo optics, jaw position, among others.

C. Flexible Circuit Electrode Assembly Including Optical Sensing System

FIGS. 195-196 illustrate a flexible circuit electrode assembly 5004comprising an optical sensing system 5014 comprising at least one lightemitting diode 5008 (LED) and photo sensor 5010 to provide an indicationof tissue status and visualization of the surgical site, according toone aspect. FIG. 195 is an elevation view of a clamp jaw assembly 5000comprising an upper jaw member 5002 a and a lower jaw member 5002 b anda flexible circuit electrode assembly 5004, according to one aspect ofthe present disclosure. The upper and lower jaw members 5002, 5002 b aremovable relative to each such that either the upper or lower jaw member5002 a, 5002 b is movable or both are movable. The flexible circuitelectrode assembly 5004 comprises an upper jaw portion 5004 a and alower portion 5004 b. The upper jaw portion 5004 a comprises onecomponent of the optical sensing system 5014, a plurality of LEDs 5008,and also may comprise an electrode. The lower jaw portion 5004 bcomprises an electrode 5006 and another component of the optical sensingsystem 5014, a photo sensor 5010, such as a photodiode, to detect thelight emitted 5016 by the LEDs 5008. The LEDs 5008, electrode 5006, andoptical sensor 5010 are coupled back to the control circuit 2402 and/orthe generator 2404 (FIG. 104).

In one aspect, one or more than one optical sensor 5010 can beincorporated into a flexible circuit electrode assembly 5004 todetermine changes in tissue 5012 condition. The monopolar or bipolar RFelectrosurgical instruments generally may use one tissue parameter,impedance, to determine the effect that the RF electricity has had onthe tissue 5012. Providing additional feedback to the control circuit2402 and/or the generator 2404 (FIG. 104) can improve the confidencelevel of the surgeon that a tissue seal has been created in the tissuebundles treated between the clamp jaw assembly 5000 of the end effectorof the electrosurgical instrument.

At least one LED 5008 located on one jaw member 5002 a, 5002 b incombination with an optical sensor 5010 (e.g., photodiode) located onanother jaw member 5002 a, 5002 b can be used to determine when thetissue seal is complete. The location of the tissue 5012 within the jawmembers 5002 a, 5002 b (distal vs. proximal), blood pressure, and forcewithin the jaw members 5002 a, 5002 b. The LED 5008 can serve a secondpurpose of providing lighting and furthering surgeon visibility.

The LED 5008 can either be comprised of organic polymers and smallmolecules or inorganic structures. In this illustration, patternableorganic LEDs 5008 are formed by vapor thermal evaporation and patternedusing stencil lithography on the flexible circuit electrode assembly5004. The photodiode optical sensor 5010 can be covered by an opticalwindow which permits only selected wavelength transmissions. The windowalso may be coated for durability, or contain one or more lenses fordifferent diffraction gradients. The photodiode optical sensor 5010 orthe LED 5008 is mounted to the trace layer of a separate flexibleprinted circuit of the flexible circuit electrode assembly 5004 whereindividual conductors are photo etched from copper or another conductor.Traces in the flexible circuit, which are connected to the photodiodeoptical sensor 5010 or the LED 5008 are routed proximally to carry thesensor current to the analog processing electronics located either inthe handle of the instrument and/or the generator. These electronics maycomprise of amplifiers, digital converters, and pass band filters, andbe part of the control circuit 2402 (FIG. 104) or the generator 2404(FIG. 104). The location and intensity of light reception by thephotodiode optical sensor 5010 can indicate the tissue thickness as wellas tissue location within the jaw members 5002 a, 5002 b of the clampjaw assembly 5000, while the LEDs 5008 can provide a secondary functionof further enhancing surgeon visualization in confined spaces.

FIG. 196 is a logic diagram 5020 of operating the optical sensing system5014 described in connection with FIG. 195, according to one aspect ofthe present disclosure. The optical sensing system 5014 controlled bythe control circuit 2402 (FIG. 104). The logic diagram 5020 will now bedescribed in connection with FIG. 195. Power is applied 5022 to the LEDs5008 and the photo sensor 5010 via a trace in the flexible circuitelectrode assembly 5004. Accordingly, light 5016 is transmitted from theLEDs 5008 through the tissue 5012 and light that is not absorbed by thetissue 5012 is detected 5024 by the photo sensor 5010. The photo sensor5010 generates an analog signal proportional to the light sensed by thephoto sensor 5010. The control circuit 2402 receives 5026 the analogsignal from the photo sensor 5010. The analog signal is filtered 5028and is provided to an digital signal processing circuits located in thehandle of the electrosurgical instrument. The digital signal processingcircuits include at least one analog-to-digital converter and a digitalsignal processor. The analog signal is converted to a digital signal andis processed 5030 by the digital signal processing circuits. The processdescribed above, can be applied to a plurality of LEDs 5008 and/or aplurality of photo sensors 5010 may be provided to evaluate tissue 5012in different location in the clamp jaw assembly 5000.

D. Flexible Circuit Electrode Including Light Pipe and LED Light Source

FIG. 197 illustrates a flexible circuit electrode assembly 5100comprising an electrode 5102 and a light pipe 5104, according to oneaspect of the present disclosure. A light source 5106 is provided totransmit light into the light pipe 5104 to illuminate the surgical siteand enhance the visibility of the surgical field of view. An LED lightsource 5106 is used in conjunction with a polymer layer acting as alight pipe 5104 to provide better illumination at the surgical site andimproved visibility of the surgical field of view. As a result thistechnique should minimize unintended tissue damage. A polymer layer 5108is incorporated into a flexible circuit electrode assembly 5100. Thepolymer layer 5108 comprises geometric features 5110 to refract theincoming light source 5106 outward to provide light 5112 to illuminatethe distal end of the electrosurgical instrument as well as thesurrounding surgical field of view.

E. Flexible Circuit Electrode Including Light Pipe and Optical FiberLight Source

FIG. 198 illustrates a flexible circuit electrode assembly 5200comprising an electrode 5202 and a light pipe 5204, according to oneaspect of the present disclosure. The light pipe 5204 comprises anoptical fiber light source 5206 to illuminate the surgical site andenhance the visibility of the surgical field of view. The flexiblecircuit electrode assembly 5200 comprises an optical fiber inconjunction with a polymer layer 5208 acting as a light pipe 5204 toilluminate the surgical site and enhance the visibility of the surgicalfield of view and as a result can minimize unintended tissue damage. Thepolymer layer 5208 is incorporated into the flexible circuit electrodeassembly 5200. The polymer layer comprises geometric features 5210 torefract the incoming light source 5206 outward to provide light 5212 toilluminate the distal end of the instrument as well as the surroundingsurgical field.

XXIII. Proximity Sensing A. Electrosurgical Instrument Equipped withInductive Element Based Proximity Sensor

The end effector portion of an electrosurgical instrument can beequipped with an inductive element to implement an inductance basedproximity sensor. It is advantageous to understand the position of amoving jaw member of the clamp jaw assembly of an end effector portionof an electrosurgical instrument relative to the opposite jaw member.This information allows the electrosurgical instrument to determine orinfer the location of the tissue, the tissue type, or the intended use,and adjust the output of the electrosurgical instrument accordingly

A flexible circuit electrode assembly may comprise a continuous wirelooped through multiple layers that can be accomplished by printing onelayer and folding over to create an inductive coil. The circuitcomprises a lead and return as two connections to the proximal end ofthe electrode and is anchored to two separate insulated wires that runproximally to the handle. No additional circuitry is needed at thedistal end of the electrode. A small current is applied by the controlcircuit 2401 and/or the generator 2404 (FIG. 104) to the inductive coiland to monitor its return. The return from the inductive coil will beindicative of the position of other metallic objects near the electrode,mainly the other jaw member of the electrosurgical instrument. If theinductor indicates an excessively large distance for the other jawmember it can infer that extraordinarily thick tissue is present, orthat the surgeon is intentionally feathering on thick tissue withoutover compressing it. The electrosurgical instrument can use thisinformation to increase its output current knowing that there will bemore resistance due to the tissue thickness.

Additionally, the inductor can be custom calibrated for how much thefield is modified based on the position of the jaw member during themanufacturing process. Equipment could control the position of the jawmember, either as a sub-assembly, or a full device assembly, and monitorthe inductive response at different positions. The resultant calibrationcan be recorded as a parameter on the device's specific EEPROM.

B. Proximity Sensor System Including Inductive Element Formed on aFlexible Circuit

FIGS. 199-208 illustrate a proximity sensor system 5300 comprising aninductive element 5302 formed on a flexible circuit 5304, according toone aspect of the present disclosure. The proximity sensor system 5300also comprises an inductance-to-digital converter circuit 5306.

FIG. 199 is a schematic diagram of a proximity sensor system 5300configured to measure axial distance “d” to a target 5322, according toone aspect of the present disclosure. The proximity sensor system 5300comprises an inductive element 5302 formed on a flexible circuit 5304.The inductive element 5302 is coupled to an inductance-to-digitalconverter circuit 5306 to convert the analog signal from the inductiveelement 5302 to a digital signal, which can then be digitally processedby the control circuit 2402 (FIG. 104).

FIG. 200 is a functional block diagram of the proximity sensor system5300, according to one aspect of the present disclosure. The inductiveelement 5302 can be modeled as an inductor L in series with a resistorRp and in parallel with a capacitor C. The inductive element 5302 iscoupled to the inductance-to-digital converter circuit 5306. The signalis received by an inductance-to-digital converter 5308. The digitaloutput of the inductance-to-digital converter 5308 is coupled to athreshold detector 5310, a proximity data register 5312, and a frequencycounter data register 5314. The outputs from the threshold detector5310, proximity data register 5312, and frequency counter data register5314 are provided to a 4-wire serial interface 5320 for communicationpurposes. A frequency counter 5316 is coupled to the frequency counterdata register 5314. The inductance-to-digital converter circuit 5306comprises a power section 5318 to condition the power for the inductiveelement 5302.

The inductance-to-digital converter circuit 5308 measures the parallelimpedance of the LC resonator of the inductive element 5302. Itaccomplishes this task by regulating the oscillation amplitude in aclosed-loop configuration to a constant level, while monitoring theenergy dissipated by the resonator. By monitoring the amount of powerinjected into the resonator, the circuit 5308 can determine the value ofRp and it returns this as a digital value which is inverselyproportional to Rp. The threshold detector 5310 block provides acomparator with hysteresis. With the threshold registers programed andcomparator enabled, the proximity data register 5312 is compared withthreshold registers and indicates the output. The circuit 5308 has asimple 4-wire serial interface 5320.

FIG. 201 is a simplified circuit model of the proximity sensor system5300 and a proximal metal target 5322, according to one aspect of thepresent disclosure. An AC source 5323 provides an alternating currentthat flows through a coil L will generate an alternating current (AC)magnetic field. If a conductive material, such as a metal target 5322,is brought into the vicinity of the coil L, this magnetic field willinduce circulating currents (eddy currents) on the surface of thetarget. These eddy currents are a function of the distance, size, andcomposition of the target 5322. The eddy currents then generate theirown magnetic field, which opposes the original field generated by thecoil L. This mechanism is best compared to a transformer, where the coilis the primary core and the eddy current is the secondary core. Theinductive coupling between both cores depends on distance and shape.Hence the resistance and inductance of the secondary core (eddycurrent), shows up as a distant dependent resistive and inductivecomponent on the primary side (coil).

FIG. 202 is a simplified circuit model of a metal target 5322 modeled asan inductor L_(T) and resistor R_(T) with circulating eddy currents5325, according to one aspect of the present disclosure. The eddycurrents 5325 generated on the surface of the target 5322 can be modeledas a transformer. The coupling 5324 between the primary and secondarycoils is a function of the distance “d” and the conductor'scharacteristics. The inductance Ls is the inductance of the coil L shownin FIG. 201 and Rs is the parasitic series resistance of the coil Lshown FIG. 201. The inductance L(d), which is a function of distance “d”is the coupled inductance of the metal target 5322. Likewise, R(d) isthe parasitic resistance of the eddy currents and is also a function ofdistance.

FIG. 203 is a schematic diagram of a linear position sensing system 5330comprising an inductive element 5302 formed on a flexible circuit 5304and an inductance-to-digital converter circuit 5308, according to oneaspect of the present disclosure. The inductive element 5302 can beformed on a flexible circuit 5304 and installed in a jaw member of aclamp arm assembly in accordance with the present disclosure. Theinductive element 5302 is coupled to the inductance-to-digital convertercircuit 5308 by a capacitor C. The output of the inductance-to-digitalconverter circuit 5308 is a linear representation of the position of aconductive target 5332 relative to the inductive element 5302.

FIG. 204 is a graphical representation 5334 of the linear positionsensing system 5330 shown in FIG. 203, according to one aspect of thepresent disclosure. The vertical axis is the digital output of theinductance-to-digital converter circuit 5308 and the horizontal axisrepresents the position of the conductive target 5332 relative to theinductive element 5302.

FIG. 205 is a schematic diagram of an angular position sensing system5340 comprising a flexible circuit inductive element 5302 formed on aflexible circuit 5304 and an inductance-to-digital converter circuit5308, according to one aspect of the present disclosure. The inductiveelement 5302 can be formed on a flexible circuit and installed in a jawmember of a clamp arm assembly. The inductive element 5302 is coupled tothe inductance-to-digital converter circuit 5308 by a capacitor C. Theoutput of the inductance-to-digital converter circuit 5308 is a sawtooth waveform that represents the angular position of a conductivetarget 5342 relative to the inductive element 5302. The saw tooth graphthat is linear output over a 360° range.

FIG. 206 is a graphical representation 5346 of the angular positionsensing system 5340 shown in FIG. 203, according to one aspect of thepresent disclosure. The vertical axis is the digital output of theinductance-to-digital converter circuit 5308 and the horizontal axisrepresents the angular position (deg) of the conductive target 5342relative to the inductive element 5302.

FIG. 207 is an upper layer layout 5350 of the inductive element 5302formed on a flexible circuit 5304 and an inductance-to-digital convertercircuit 5308 and FIG. 208 is a lower layer layout 5352 of the inductiveelement 5302 formed on a flexible circuit 5304 and aninductance-to-digital converter circuit 5308.

XXIV. Flexible Circuit Electrodes Coated with Insulation

FIGS. 209-210 illustrate examples of flexible circuit electrodes coatedwith ultraviolet (U.V.) cured paint insulation systems, according to oneaspect of the present disclosure.

FIG. 209 illustrates a coating process 5400 for applying a dielectricmaterial 5402 on an electrical connection 5404 or joint between aflexible circuit electrode assembly 5406 and an electrical conductor5408 with, according to one aspect of the present disclosure. A firstmask 5410 is provided over the flexible circuit electrode assembly 5406and a second mask 5412 is provided over the other circuit elements suchas the electrical conductor 5408, which is tied to ground 5414 duringthe coating process. An electrospray nozzle 5416 is used for a localizedapplication of a small amount of dielectric material 5402 in paint onthe electrical connection 5404. Spraying the dielectric material 5402 inpaint form or lacquer form leaves no gaps in the coating. In one aspect,transfer windings are coated in lacquer to prevent shorting. Theelectrical connection 5404 is coated in lacquer and all exposed metalsurfaces all electro-sprayed.

FIG. 210 is an electrical schematic diagram 5420 of the electrosprayprocess, according to one aspect of the present disclosure. As shown inFIG. 210, an electrospray nozzle 5416 is positively charged to a highvoltage, e.g., +100V. An active rod target 5422, such as the electricalconnection 5404 shown in FIG. 209, to be coated is tied to ground 5414.When the electrospray nozzle 5410 is activated, it releases chargedlacquer particles 5424, which coat the target 5422.

XXV. Heating, Cutting with Heat, and Cooling A. Temperature SensorOvermolded with Flexible Circuit Electrode

FIGS. 211-215 illustrate temperature sensor overmolded with a flexiblecircuit electrode assembly located in a jaw member to provide abiocompatible clamp jaw assembly, according to one aspect of the presentdisclosure. Temperature sensors can be disposed in a clamp jaw assemblyto provide real time accurate measurement of temperature at the jawmember and can provide improved tissue temperature control when used tocontrol device power output and seal termination. Biocompatibility ofsensor material, wire protection and routing, and assembly difficultiesprevent simple integration of temperature sensors (or other sensors:force, light etc.) in the jaw member. Biocompatibility of thermistormaterial, wire protection and routing, and assembly difficulties preventsimple integration of temperature sensor or other sensors types.

Thermistors would provide real time accurate measurement of temperatureat the jaw and can provide improved tissue temperature control when usedto control device power output and seal termination. The temperaturesensors can be soldered, adhered, or placed on the electrode lower withan injection molding tool to inject insulator material (glass filledpolyamide for example) around wires to lock them in place. Encapsulatedsensors and wires keep patient safe and improve assembly. Better controlof power can improve seal strength and procedural efficiency. In oneaspect, a configuration and method of manufacturing a flexible circuitelectrode assembly comprising embedded temperature sensor in a monopolaror bipolar RF vessel sealer clamp jaw assembly are provided.

FIG. 211 is a perspective view of a clamp jaw assembly 5500 configuredfor an electrosurgical instrument tissue sealer comprising an embeddedtemperature sensor 5506, according to one aspect of the presentdisclosure. The clamp jaw assembly 5500 comprises an upper jaw member5502 a and a lower jaw member 5502 b. The upper and lower jaw members5502 a, 5502 b are movable relative to each other. One or both jawmember 5502 a, 5502 b may be movable. The temperature sensor 5506 can beovermolded with a flexible circuit electrode assembly 5504. The flexiblecircuit electrode assembly 5504 may be located in at least one of thejaw members 5502 a, 5502 b or both. A knife slot 5508 is provided in atleast one jaw member 5502 b to enable a knife to reciprocate therealong.A plurality of elements or stop members 5518 are formed on the tissuecontacting surface 5512 of the flexible circuit electrode assembly 5504.

FIG. 212 is a plan view of the flexible circuit electrode assembly 5504comprising an embedded temperature sensor 5506 overmolded therewith,according to one aspect of the present disclosure. The flexible circuitelectrode assembly 5504 comprises an electrode 5510 on a tissuecontacting surface 5512 and one or more embedded temperatures sensor5506 located just below the tissue contacting surface 5512. A firstelectrical connector 5514 is provided to supply power to and read asignal from the temperature sensor 5506. A second connector 5516 isprovided to supply power to the electrode 5510.

FIG. 213 is a perspective view from the proximal end of the flexiblecircuit electrode assembly 5504 with a temperature sensor 5506overmolded therewith, according to one aspect of the present disclosure.The knife slot 5508, the tissue contacting surface 5512, and the firstand second electrical connectors 5514, 5516 also are shown.

FIG. 214 is a section view of the flexible circuit electrode assembly5504 with a temperature sensor 5506 overmolded therewith taken alongsection line 214-214 as shown in FIG. 213, according to one aspect ofthe present disclosure. The section view illustrates the electricalcontact elements 5514 that supply power to and carry signals to and/orfrom the temperature sensor 5506 located just below the tissuecontacting surface 5512.

FIG. 215 is a section view of the flexible circuit electrode assembly5504 with a temperature sensor 5506 overmolded therewith taken alongsection line 215-215 as shown in FIG. 214, according to one aspect ofthe present disclosure. This view shows the lower portion 5524 of theflexible circuit electrode assembly 5504 that is attached to the lowerjaw member 5502 b of the clamp arm assembly 5500. Recesses or apertures5520 are formed in the lower portion 5524 of the flexible circuitelectrode assembly 5502 b that houses the temperature sensor 5506. FIG.215 also provides another view of the electrical contact elements 5514located below the tissue contacting surface 5512 and the knife slot5508.

B. Flexible Circuit Electrode Including RF Electrode with TissueContacting Surface and Heater Element to Create Dual Energy Source forTreating Tissue

FIG. 216 illustrates a flexible circuit electrode assembly 5600comprising a RF electrode 5602 with a tissue contacting surface and aheater element 5604 thus creating a dual energy source for treatingtissue, according to one aspect of the present disclosure. In oneaspect, a vapor film with high resistance zones is deposited on a layerbeneath the exposed RF electrode 5602 to form a resistive heating layer5604. The electrode 5602 may be formed of copper or other electricallyconductive metal. Accordingly, the electrode 5602 defines a firstheating zone to seal tissue and the resistive heating layer 5604 definesa second heating zone to raise the tissue temperature. The resistiveheating layer 5604 comprises a plurality of resistive heating elements5606. When low impedance tissue is detected on the tissue contactingsurface of the electrode 5602, the resistive heating layer 5604 can beactivated. Heat from the resistive heating layer 5604 works inconjunction with the RF energy from the electrode 5602 to raise thetissue temperature to a water desiccating temperature. This provides atechnique for heating low impedance tissues in an RF electrosurgicalinstrument tissue sealer. An electrically insulative layer 5608 isdisposed between the electrode 5602 and the resistive heating layer5604. The flexible circuit electrode assembly 5600 is coupled to thecontrol circuit 2402 and/or the generator 2404 (FIG. 104) to detect thelow impedance tissue disposed on the electrode 5602 and to drive acurrent through the resistive heating layer 5604 to control itstemperature.

C. Process of Sealing, Cooling, and Cutting Tissue While Cooling

Electrosurgical instruments generally depend on mechanical force inputfrom the surgeon to drive a knife to cut tissue. An electric knifeincreases ease of operation, but a conventional electric knife may besubject to excessive heat spread to the tissue. Thus, an electricalknife alone may not provide the best results because of tissueoverheating concerns. Employing flexible circuit technology, however, itis more practical to incorporate MEMS based cooling cells to offsetincreased heat spread from the electric knife. The surgeon wouldexperience ease of use because they only need to push a button toactivate the electric knife and the cooling cells.

FIGS. 217-219 illustrate a process of sealing, cooling, and cuttingtissue wile cooling, according to one aspect of the present disclosure.The process may be carried out with a clamp jaw assembly comprising anupper jaw member and a lower jaw member and a flexible circuit electrodeassembly comprising an electric knife, one or more cooling cells, andone or more electrodes disclosure. The electrodes may be disposed eitherin the upper or lower jaw member, or both, and are provided to make atissue seal. The upper and lower jaw members are movable relative toeach other, where either one of the upper and lower jaws are movable orboth are movable. The electric knife and/or the cooling cells can beimplemented with superconducting heat and/or microelectromechanicalsystems (MEMS) cooling cells. The electrosurgical instrument employs aflexible circuit electrode assembly that contains multiple circuits suchas electrodes for sealing the tissue, an electric knife for cutting thetissue, and cooling cells the cooling the tissue. The electrodes,electric knife, and cooling cells ae coupled to the control circuit 2402and/or the generator 2404 (FIG. 104) to control the operation of each ofthe separate circuits controlling sealing, cooling, and cutting tissue.

FIG. 217 is a section view of a clamp jaw assembly 5700 in the processof performing a first step of sealing tissue disposed in the clamp jawassembly 5700, according to one aspect of the present disclosure. Thecircuits disposed on the flexile circuit electrode are configured aselectrodes to seal tissue using RF energy via electrodes 5702 a, 5702 b.

FIG. 218 is a section view of the clamp jaw assembly 5700 shown in FIG.217 in the process of performing a second step of cooling the tissuedisposed in the clamp jaw assembly, according to one aspect of thepresent disclosure. The circuits disposed on the flexile circuitelectrode are configured as cooling cells 5704 a, 5704 b to cool thetissue by activating the MEMS elements. Next both pads would activateMEM cooling cells, which would have thermal reservoirs attached to asuper conductive bar that runs the length of the shaft to a coldreservoir in the handle. This bar would be insulated along the length ofthe shaft.

FIG. 219 is a section view of the clamp jaw assembly 5700 shown in FIG.217 in the process of performing a third step of cooling and cutting thetissue disposed in the clamp jaw assembly, according to one aspect ofthe present disclosure. The circuits disposed on the flexile circuitelectrode are configured as a MEMS electric knife between electrode 5706a, 5706 b to cut the tissue while limiting the thermal spread in thetissue with cooling cells 5708, and thus eliminating the need for amechanical knife. While the cooling cells 5708 are activated, a thirdcircuit is triggered to transect or cut the tissue between electrodes5706 a, 5706 b, isolating thermal energy to the region intended to becut. Thus transecting tissue with minimal thermal spread to neighboringtissue. This would make an electric knife a viable solution withoutexcessive tissue damage.

While the examples herein are described mainly in the context ofelectrosurgical instruments, it should be understood that the teachingsherein may be readily applied to a variety of other types of medicalinstruments. By way of example only, the teachings herein may be readilyapplied to tissue graspers, tissue retrieval pouch deployinginstruments, surgical staplers, ultrasonic surgical instruments, etc. Itshould also be understood that the teachings herein may be readilyapplied to any of the instruments described in any of the referencescited herein, such that the teachings herein may be readily combinedwith the teachings of any of the references cited herein in numerousways. Other types of instruments into which the teachings herein may beincorporated will be apparent to those of ordinary skill in the art.

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference. Any material, or portion thereof, thatis said to be incorporated by reference herein, but which conflicts withexisting definitions, statements, or other disclosure material set forthherein will only be incorporated to the extent that no conflict arisesbetween that incorporated material and the existing disclosure material.

Aspects of the devices disclosed herein can be designed to be disposedof after a single use, or they can be designed to be used multipletimes. Aspects may, in either or both cases, be reconditioned for reuseafter at least one use. Reconditioning may include any combination ofthe steps of disassembly of the device, followed by cleaning orreplacement of particular pieces, and subsequent reassembly. Inparticular, aspects of the device may be disassembled, and any number ofthe particular pieces or parts of the device may be selectively replacedor removed in any combination. Upon cleaning and/or replacement ofparticular parts, aspects of the device may be reassembled forsubsequent use either at a reconditioning facility, or by a surgicalteam immediately prior to a surgical procedure. Those skilled in the artwill appreciate that reconditioning of a device may utilize a variety oftechniques for disassembly, cleaning/replacement, and reassembly. Use ofsuch techniques, and the resulting reconditioned device, are all withinthe scope of the present application.

By way of example only, aspects described herein may be processed beforesurgery. First, a new or used instrument may be obtained and ifnecessary cleaned. The instrument may then be sterilized. In onesterilization technique, the instrument is placed in a closed and sealedcontainer, such as a plastic or TYVEK bag. The container and instrumentmay then be placed in a field of radiation that can penetrate thecontainer, such as gamma radiation, x-rays, or high-energy electrons.The radiation may kill bacteria on the instrument and in the container.The sterilized instrument may then be stored in the sterile container.The sealed container may keep the instrument sterile until it is openedin a medical facility. A device may also be sterilized using any othertechnique known in the art, including but not limited to beta or gammaradiation, ethylene oxide, or steam.

Having shown and described various aspects of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, aspects, geometrics, materials, dimensions, ratios, steps, andthe like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

While various details have been set forth in the foregoing description,it will be appreciated that the various aspects of the flexible circuitsfor electrosurgical instrument may be practiced without these specificdetails. For example, for conciseness and clarity selected aspects havebeen shown in block diagram form rather than in detail. Some portions ofthe detailed descriptions provided herein may be presented in terms ofinstructions that operate on data that is stored in a computer memory.Such descriptions and representations are used by those skilled in theart to describe and convey the substance of their work to others skilledin the art. In general, an algorithm refers to a self-consistentsequence of steps leading to a desired result, where a “step” refers toa manipulation of physical quantities which may, though need notnecessarily, take the form of electrical or magnetic signals capable ofbeing stored, transferred, combined, compared, and otherwisemanipulated. It is common usage to refer to these signals as bits,values, elements, symbols, characters, terms, numbers, or the like.These and similar terms may be associated with the appropriate physicalquantities and are merely convenient labels applied to these quantities.

Unless specifically stated otherwise as apparent from the foregoingdiscussion, it is appreciated that, throughout the foregoingdescription, discussions using terms such as “processing” or “computing”or “calculating” or “determining” or “displaying” or the like, refer tothe action and processes of a computer system, or similar electroniccomputing device, that manipulates and transforms data represented asphysical (electronic) quantities within the computer system's registersand memories into other data similarly represented as physicalquantities within the computer system memories or registers or othersuch information storage, transmission or display devices.

It is worthy to note that any reference to “one aspect,” “an aspect,”“one aspect,” or “an aspect” means that a particular feature, structure,or characteristic described in connection with the aspect is included inat least one aspect. Thus, appearances of the phrases “in one aspect,”“in an aspect,” “in one aspect,” or “in an aspect” in various placesthroughout the specification are not necessarily all referring to thesame aspect. Furthermore, the particular features, structures orcharacteristics may be combined in any suitable manner in one or moreaspects.

Although various aspects have been described herein, many modifications,variations, substitutions, changes, and equivalents to those aspects maybe implemented and will occur to those skilled in the art. Also, wherematerials are disclosed for certain components, other materials may beused. It is therefore to be understood that the foregoing descriptionand the appended claims are intended to cover all such modifications andvariations as falling within the scope of the disclosed aspects. Thefollowing claims are intended to cover all such modification andvariations.

Some or all of the aspects described herein may generally comprisetechnologies for flexible circuits for electrosurgical instrument, orotherwise according to technologies described herein. In a generalsense, those skilled in the art will recognize that the various aspectsdescribed herein which can be implemented, individually and/orcollectively, by a wide range of hardware, software, firmware, or anycombination thereof can be viewed as being composed of various types of“electrical circuitry.” Consequently, as used herein “electricalcircuitry” includes, but is not limited to, electrical circuitry havingat least one discrete electrical circuit, electrical circuitry having atleast one integrated circuit, electrical circuitry having at least oneapplication specific integrated circuit, electrical circuitry forming ageneral purpose computing device configured by a computer program (e.g.,a general purpose computer configured by a computer program which atleast partially carries out processes and/or devices described herein,or a microprocessor configured by a computer program which at leastpartially carries out processes and/or devices described herein),electrical circuitry forming a memory device (e.g., forms of randomaccess memory), and/or electrical circuitry forming a communicationsdevice (e.g., a modem, communications switch, or optical-electricalequipment). Those having skill in the art will recognize that thesubject matter described herein may be implemented in an analog ordigital fashion or some combination thereof.

The foregoing detailed description has set forth various aspects of thedevices and/or processes via the use of block diagrams, flowcharts,and/or examples. Insofar as such block diagrams, flowcharts, and/orexamples contain one or more functions and/or operations, it will beunderstood by those within the art that each function and/or operationwithin such block diagrams, flowcharts, or examples can be implemented,individually and/or collectively, by a wide range of hardware, software,firmware, or virtually any combination thereof. In one aspect, severalportions of the subject matter described herein may be implemented viaApplication Specific Integrated Circuits (ASICs), Field ProgrammableGate Arrays (FPGAs), digital signal processors (DSPs), or otherintegrated formats. Those skilled in the art will recognize, however,that some aspects of the aspects disclosed herein, in whole or in part,can be equivalently implemented in integrated circuits, as one or morecomputer programs running on one or more computers (e.g., as one or moreprograms running on one or more computer systems), as one or moreprograms running on one or more processors (e.g., as one or moreprograms running on one or more microprocessors), as firmware, or asvirtually any combination thereof, and that designing the circuitryand/or writing the code for the software and or firmware would be wellwithin the skill of one of skill in the art in light of this disclosure.In addition, those skilled in the art will appreciate that themechanisms of the subject matter described herein are capable of beingdistributed as a program product in a variety of forms, and that anillustrative aspect of the subject matter described herein appliesregardless of the particular type of signal bearing medium used toactually carry out the distribution. Examples of a signal bearing mediuminclude, but are not limited to, the following: a recordable type mediumsuch as a floppy disk, a hard disk drive, a Compact Disc (CD), a DigitalVideo Disk (DVD), a digital tape, a computer memory, etc.; and atransmission type medium such as a digital and/or an analogcommunication medium (e.g., a fiber optic cable, a waveguide, a wiredcommunications link, a wireless communication link (e.g., transmitter,receiver, transmission logic, reception logic, etc.), etc.).

All of the above-mentioned U.S. patents, U.S. patent applicationpublications, U.S. patent applications, foreign patents, foreign patentapplications, non-patent publications referred to in this specificationand/or listed in any Application Data Sheet, or any other disclosurematerial are incorporated herein by reference, to the extent notinconsistent herewith. As such, and to the extent necessary, thedisclosure as explicitly set forth herein supersedes any conflictingmaterial incorporated herein by reference. Any material, or portionthereof, that is said to be incorporated by reference herein, but whichconflicts with existing definitions, statements, or other disclosurematerial set forth herein will only be incorporated to the extent thatno conflict arises between that incorporated material and the existingdisclosure material.

One skilled in the art will recognize that the herein describedcomponents (e.g., operations), devices, objects, and the discussionaccompanying them are used as examples for the sake of conceptualclarity and that various configuration modifications are contemplated.Consequently, as used herein, the specific exemplars set forth and theaccompanying discussion are intended to be representative of their moregeneral classes. In general, use of any specific exemplar is intended tobe representative of its class, and the non-inclusion of specificcomponents (e.g., operations), devices, and objects should not be takenlimiting.

With respect to the use of substantially any plural and/or singularterms herein, those having skill in the art can translate from theplural to the singular and/or from the singular to the plural as isappropriate to the context and/or application. The varioussingular/plural permutations are not expressly set forth herein for sakeof clarity.

The herein described subject matter sometimes illustrates differentcomponents contained within, or connected with, different othercomponents. It is to be understood that such depicted architectures aremerely exemplary, and that in fact many other architectures may beimplemented which achieve the same functionality. In a conceptual sense,any arrangement of components to achieve the same functionality iseffectively “associated” such that the desired functionality isachieved. Hence, any two components herein combined to achieve aparticular functionality can be seen as “associated with” each othersuch that the desired functionality is achieved, irrespective ofarchitectures or intermedial components. Likewise, any two components soassociated can also be viewed as being “operably connected,” or“operably coupled,” to each other to achieve the desired functionality,and any two components capable of being so associated can also be viewedas being “operably couplable,” to each other to achieve the desiredfunctionality. Specific examples of operably couplable include but arenot limited to physically mateable and/or physically interactingcomponents, and/or wirelessly interactable, and/or wirelesslyinteracting components, and/or logically interacting, and/or logicallyinteractable components.

Some aspects may be described using the expression “coupled” and“connected” along with their derivatives. It should be understood thatthese terms are not intended as synonyms for each other. For example,some aspects may be described using the term “connected” to indicatethat two or more elements are in direct physical or electrical contactwith each other. In another example, some aspects may be described usingthe term “coupled” to indicate that two or more elements are in directphysical or electrical contact. The term “coupled,” however, also maymean that two or more elements are not in direct contact with eachother, but yet still co-operate or interact with each other.

In some instances, one or more components may be referred to herein as“configured to,” “configurable to,” “operable/operative to,”“adapted/adaptable,” “able to,” “conformable/conformed to,” etc. Thoseskilled in the art will recognize that “configured to” can generallyencompass active-state components and/or inactive-state componentsand/or standby-state components, unless context requires otherwise.

While particular aspects of the present subject matter described hereinhave been shown and described, it will be apparent to those skilled inthe art that, based upon the teachings herein, changes and modificationsmay be made without departing from the subject matter described hereinand its broader aspects and, therefore, the appended claims are toencompass within their scope all such changes and modifications as arewithin the true spirit and scope of the subject matter described herein.It will be understood by those within the art that, in general, termsused herein, and especially in the appended claims (e.g., bodies of theappended claims) are generally intended as “open” terms (e.g., the term“including” should be interpreted as “including but not limited to,” theterm “having” should be interpreted as “having at least,” the term“includes” should be interpreted as “includes but is not limited to,”etc.). It will be further understood by those within the art that if aspecific number of an introduced claim recitation is intended, such anintent will be explicitly recited in the claim, and in the absence ofsuch recitation no such intent is present. For example, as an aid tounderstanding, the following appended claims may contain usage of theintroductory phrases “at least one” and “one or more” to introduce claimrecitations. However, the use of such phrases should not be construed toimply that the introduction of a claim recitation by the indefinitearticles “a” or “an” limits any particular claim containing suchintroduced claim recitation to claims containing only one suchrecitation, even when the same claim includes the introductory phrases“one or more” or “at least one” and indefinite articles such as “a” or“an” (e.g., “a” and/or “an” should typically be interpreted to mean “atleast one” or “one or more”); the same holds true for the use ofdefinite articles used to introduce claim recitations.

In addition, even if a specific number of an introduced claim recitationis explicitly recited, those skilled in the art will recognize that suchrecitation should typically be interpreted to mean at least the recitednumber (e.g., the bare recitation of “two recitations,” without othermodifiers, typically means at least two recitations, or two or morerecitations). Furthermore, in those instances where a conventionanalogous to “at least one of A, B, and C, etc.” is used, in generalsuch a construction is intended in the sense one having skill in the artwould understand the convention (e.g., “a system having at least one ofA, B, and C” would include but not be limited to systems that have Aalone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). In those instances where aconvention analogous to “at least one of A, B, or C, etc.” is used, ingeneral such a construction is intended in the sense one having skill inthe art would understand the convention (e.g., “a system having at leastone of A, B, or C” would include but not be limited to systems that haveA alone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). It will be furtherunderstood by those within the art that typically a disjunctive wordand/or phrase presenting two or more alternative terms, whether in thedescription, claims, or drawings, should be understood to contemplatethe possibilities of including one of the terms, either of the terms, orboth terms unless context dictates otherwise. For example, the phrase “Aor B” will be typically understood to include the possibilities of “A”or “B” or “A and B.”

With respect to the appended claims, those skilled in the art willappreciate that recited operations therein may generally be performed inany order. Also, although various operational flows are presented in asequence(s), it should be understood that the various operations may beperformed in other orders than those which are illustrated, or may beperformed concurrently. Examples of such alternate orderings may includeoverlapping, interleaved, interrupted, reordered, incremental,preparatory, supplemental, simultaneous, reverse, or other variantorderings, unless context dictates otherwise. Furthermore, terms like“responsive to,” “related to,” or other past-tense adjectives aregenerally not intended to exclude such variants, unless context dictatesotherwise.

In certain cases, use of a system or method may occur in a territoryeven if components are located outside the territory. For example, in adistributed computing context, use of a distributed computing system mayoccur in a territory even though parts of the system may be locatedoutside of the territory (e.g., relay, server, processor, signal-bearingmedium, transmitting computer, receiving computer, etc. located outsidethe territory).

A sale of a system or method may likewise occur in a territory even ifcomponents of the system or method are located and/or used outside theterritory. Further, implementation of at least part of a system forperforming a method in one territory does not preclude use of the systemin another territory.

Although various aspects have been described herein, many modifications,variations, substitutions, changes, and equivalents to those aspects maybe implemented and will occur to those skilled in the art. Also, wherematerials are disclosed for certain components, other materials may beused. It is therefore to be understood that the foregoing descriptionand the appended claims are intended to cover all such modifications andvariations as falling within the scope of the disclosed aspects. Thefollowing claims are intended to cover all such modification andvariations.

In summary, numerous benefits have been described which result fromemploying the concepts described herein. The foregoing description ofthe one or more aspects has been presented for purposes of illustrationand description. It is not intended to be exhaustive or limiting to theprecise form disclosed. Modifications or variations are possible inlight of the above teachings. The one or more aspects were chosen anddescribed in order to illustrate principles and practical application tothereby enable one of ordinary skill in the art to utilize the variousaspects and with various modifications as are suited to the particularuse contemplated. It is intended that the claims submitted herewithdefine the overall scope.

What is claimed is:
 1. A method of manufacturing a flexible circuitelectrode, the method comprising: laminating a flexible electricallyconductive sheet to a flexible electrically insulative sheet with anadhesive therebetween to produce a flexible laminate; forming at leastone electrode on the flexible electrically conductive sheet; forming atleast one electrically insulative layer on a tissue contacting surfaceof the least one electrode; and separating the at least one electrodefrom the flexible laminate.
 2. The method of claim 1, wherein theflexible electrically conductive sheet is selected from any one ofcopper, gold plated copper, silver, platinum, stainless steel, oraluminum, or alloys thereof.
 3. The method of claim 1, wherein theflexible electrically insulative sheet is selected from any one ofpolyimide, polyester, fluorocarbon, or any polymeric material, or anycombinations thereof.
 4. The method of claim 1, wherein forming the atleast one electrode on the flexible electrically conductive sheetcomprises etching at least one electrode on the flexible electricallyconductive sheet.
 5. The method of claim 4, wherein etching comprises:screen printing a protective barrier on the flexible electricallyconductive sheet; and photoetching away any remaining material whichdoes not make up a final shape of the at least one electrode.
 6. Themethod of claim 5, wherein the at least one electrically insulativelayer further defines the at least one electrode.
 7. The method of claim1, wherein the at least one electrically insulative layer defines atleast one electrically insulative element.
 8. The method of claim 7,wherein the at least one electrically insulative element is configuredas a spacer.
 9. The method of claim 1, wherein forming the at least oneelectrically insulative layer comprises printing a dielectric materialon the tissue contacting surface of the at least one electrode.
 10. Themethod of claim 1, wherein forming the at least one electricallyinsulative layer comprises bonding a dielectric cover film on the tissuecontacting surface of the at least one electrode.
 11. The method ofclaim 10, further comprising forming a spacer by etching the dielectriccover film bonded to the tissue contacting surface of the at least oneelectrode.
 12. The method of claim 1, wherein forming the at least oneelectrically insulative layer comprises printing at least one dielectricnonstick element on a tissue contacting surface of the at least oneelectrode.
 13. The method of claim 12, wherein printing the at least onedielectric nonstick element comprises printing an annular wall on thetissue contacting surface of the at least one electrode, wherein theannular wall defines a cavity.
 14. The method of claim 1, whereinforming the at least one electrically insulative layer comprisesprinting at least one dielectric nonstick element on a tissue contactingsurface of the at least one electrode.
 15. The method of claim 1,wherein forming the at least one electrically insulative layer on thetissue contacting surface of the at least one electrode comprisesprinting at least one electrically insulative element sized andconfigured to define a predetermined gap between opposing jaw members ofa clamp jaw assembly.
 16. The method of claim 1, wherein forming the atleast one electrically insulative layer on the tissue contacting surfaceof the at least one electrode comprises printing at least oneelectrically insulative pattern of electrically insulative elements onthe tissue contacting surface of the at least one electrode.
 17. Themethod of claim 1, wherein separating the at least one electrodecomprises die cutting the at least one electrode from the flexiblelaminate.
 18. The method of claim 1, wherein forming the at least oneelectrode comprises forming a distal electrode element on a distal endof the at least one electrode.
 19. The method of claim 18, whereinforming the distal electrode element comprises forming a distalelectrode element that is electrically coupled to the at least oneelectrode.
 20. The method of claim 18, wherein forming the distalelectrode element comprises forming a distal electrode element that iselectrically isolated from the at least one electrode.
 21. The method ofclaim 1, wherein forming the at least one electrode comprises forming atleast two electrode segments electrically isolated from each other by agap.
 22. The method of claim 1, wherein forming the at least oneelectrode comprises forming at least two electrode segments connected bya flexure bearing.
 23. The method of claim 22, wherein forming the leasttwo electrode segments connected by the flexure bearing comprisesforming the at least two electrode segments spaced apart laterallyrelative to the flexure bearing on the at least one electrode.
 24. Themethod of claim 22, wherein forming the least two electrode segmentsconnected by a flexure bearing comprises forming the at least twoelectrode segments are spaced apart longitudinally relative to theflexure bearing on the at least one electrode.
 25. The method of claim1, wherein: forming at least one electrode on the flexible electricallyconductive sheet comprises forming a plurality of electrodes on theflexible electrically conductive sheet; and forming at least oneelectrically insulative layer on a tissue contacting surface of theleast one electrode comprises forming the at least one electricallyinsulative layer on a tissue contacting surface of each of the pluralityof electrodes.
 26. A flexible circuit electrode formed by a process,comprising: laminating a flexible electrically conductive sheet to aflexible electrically insulative sheet with adhesive therebetween toproduce a flexible laminate; forming at least one electrode on theflexible electrically conductive sheet; forming at least oneelectrically insulative layer on a tissue contacting surface of theleast one electrode; and separating the at least one electrode from theflexible laminate.
 27. The flexible circuit electrode of claim 26,wherein the flexible electrically conductive sheet is selected from anyone of copper, gold plated copper, silver, platinum, stainless steel, oraluminum, or alloys thereof.
 28. The flexible circuit electrode of claim26, wherein the flexible electrically insulative sheet is selected fromany one of polyimide, polyester, fluorocarbon, or any polymericmaterial, or any combinations thereof.
 29. The flexible circuitelectrode of claim 26, wherein forming the at least one electrode on theflexible electrically conductive sheet comprises etching at least oneelectrode on the flexible electrically conductive sheet.
 30. Theflexible circuit electrode of claim 29, wherein etching comprises:screen printing a protective barrier on the flexible electricallyconductive sheet; and photoetching away any remaining material whichdoes not make up a final shape of the at least one electrode.
 31. Theflexible circuit electrode of claim 30, wherein the at least oneelectrically insulative layer further defines the at least oneelectrode.
 32. The flexible circuit electrode of claim 26, wherein theat least one electrically insulative layer defines at least oneelectrically insulative element.
 33. The flexible circuit electrode ofclaim 32, wherein the at least one electrically insulative element isconfigured as a spacer.
 34. The flexible circuit electrode of claim 26,wherein forming the at least one electrically insulative layer comprisesprinting a dielectric material on the tissue contacting surface of theat least one electrode.
 35. The flexible circuit electrode of claim 26,wherein forming the at least one electrically insulative layer comprisesbonding a dielectric cover film on the tissue contacting surface of theat least one electrode.
 36. The flexible circuit electrode of claim 35,further comprising forming a spacer by etching the dielectric cover filmbonded to the tissue contacting surface of the at least one electrode.37. The flexible circuit electrode of claim 26, wherein forming the atleast one electrically insulative layer comprises printing at least onedielectric nonstick element on a tissue contacting surface of the atleast one electrode.
 38. The flexible circuit electrode of claim 37,wherein printing the at least one dielectric nonstick element comprisesprinting an annular wall on the tissue contacting surface of the atleast one electrode, wherein the annular wall defines a cavity.
 39. Theflexible circuit electrode of claim 26, wherein forming the at least oneelectrically insulative layer comprises printing at least one dielectricnonstick element on a tissue contacting surface of the at least oneelectrode.
 40. The flexible circuit electrode of claim 26, whereinforming the at least one electrically insulative layer on the tissuecontacting surface of the at least one electrode comprises printing atleast one electrically insulative element sized and configured to definea predetermined gap between opposing jaw members of a clamp jawassembly.
 41. The flexible circuit electrode of claim 26, whereinforming the at least one electrically insulative layer on the tissuecontacting surface of the at least one electrode comprises printing atleast one electrically insulative pattern of electrically insulativeelements on the tissue contacting surface of the at least one electrode.42. The flexible circuit electrode of claim 26, wherein separating theat least one electrode comprises die cutting the at least one electrodefrom the flexible laminate.
 43. The flexible circuit electrode of claim26, wherein forming the at least one electrode comprises forming adistal electrode element on a distal end of the at least one electrode.44. The flexible circuit electrode of claim 43, wherein forming thedistal electrode element comprises forming a distal electrode elementthat is electrically coupled to the at least one electrode.
 45. Theflexible circuit electrode of claim 43, wherein forming the distalelectrode element comprises forming a distal electrode element that iselectrically isolated from the at least one electrode.
 46. The flexiblecircuit electrode of claim 26, wherein forming the at least oneelectrode comprises forming at least two electrode segments electricallyisolated from each other by a gap.
 47. The flexible circuit electrode ofclaim 26, wherein forming the at least one electrode comprises formingat least two electrode segments connected by a flexure bearing.
 48. Theflexible circuit electrode of claim 47, wherein forming the least twoelectrode segments connected by the flexure bearing comprises formingthe at least two electrode segments spaced apart laterally relative tothe flexure bearing on the at least one electrode.
 49. The flexiblecircuit electrode of claim 47, wherein forming the least two electrodesegments connected by a flexure bearing comprises forming the at leasttwo electrode segments are spaced apart longitudinally relative to theflexure bearing on the at least one electrode.
 50. The flexible circuitelectrode of claim 26, wherein: forming at least one electrode on theflexible electrically conductive sheet comprises forming a plurality ofelectrodes on the flexible electrically conductive sheet; and forming atleast one electrically insulative layer on a tissue contacting surfaceof the least one electrode comprises forming the at least oneelectrically insulative layer on a tissue contacting surface of each ofthe plurality of electrodes.
 51. A method of manufacturing a flexiblecircuit electrode assembly, the method comprising: vacuum forming aflexible circuit; trimming the vacuum formed flexible circuit; andattaching the trimmed vacuum formed flexible circuit to a jaw member ofa clamp jaw assembly.
 52. The method of claim 51, further comprising:placing the vacuum formed flexible circuit in a molding tool; andmolding a substrate to support a profile of the vacuum formed flexiblecircuit.
 53. The method of claim 52, wherein attaching the trimmedvacuum formed flexible circuit to the jaw member of the clamp jawassembly comprises molding the trimmed vacuum formed flexible circuitover the jaw member.
 54. The method of claim 51, wherein attaching thetrimmed vacuum formed flexible circuit to the jaw member of the clampjaw assembly comprises adhering the trimmed vacuum formed flexiblecircuit to the jaw member with adhesive.